Chapter 4: Medical Terminology 2.4

Brian Litza, EdD

Chapter 4: Medical Terminology 2.4

Brian Litza, EdD

4.1 Medical Terminology

Learning Objectives

Understand commonly used medical prefixes.
Understand commonly used medical suffixes.
Understand commonly used root words.
Understand commonly used directional terms.
Understand commonly used terms associated with body systems.

Understanding medical terminology is important for anyone working in or studying healthcare fields. It can seem overwhelming at first, but medical terms follow a logical structure that, once understood, makes learning them much easier. Most medical terms are composed of prefixes, roots, and suffixes, each of which provides important information about the term’s meaning. By breaking down complex terms into these components, one can piece together the definition. For instance, in the word “bradycardia” (“brady-” meaning slow, “-cardia” meaning heart), we can deduce it refers to a slow heart rate. This method of deconstructing terms allows for a deeper understanding and application in real-world settings.

Combining medical terms is a bit like constructing a sentence. By putting together a prefix, root word, and suffix, you can create a term that accurately describes a specific medical condition, procedure, or part of the body. Here’s how to do it:

Start with the Root Word (Body Part or System)
The root is the main part of the term, usually referring to the body part, system, or primary focus.
Example: “cardi-” refers to the heart
Add a Prefix (if needed)
The prefix comes at the beginning of the word and provides information about location, quantity, time, or status
Example: “tachy-” means “fast”. When combined with “cardi-” it forms “tachycardia,” which means “fast hear rate”.
Attach a Suffix (Condition, Disease, or Procedure)
The suffix comes at the end and describes what is happening with the body part or system, such as a condition, disease, or procedure.
Example: Adding “-itis” (inflammation) to “tonsil” (tonsil) creates “tonsilitis,” meaning inflammation of the tonsils.
Combine all parts (Prefix + Root + Suffix)
Not every term will have all three parts, but when they do, they follow this order: Prefix + Root + Suffix. Sometimes, a combining vowel (usually “o”) is added between parts for easier pronunciation.
Examples of combining prefixes, roots, and suffixes:
1. Example 1: Hypoglycemia
  Prefix: “hypo-” = low
  Root: “glyc-” = sugar
  Suffix: “-emia” = blood condition
  Hypoglycemia = low blood sugar condition
2. Example 2: Electrocardiogram
  Prefix: “electro-” = electricity
  Root: “cardi-” = heart
  Suffix: “-gram” = recording or picture
  Electrocardiogram = a recording of the heart’s electrical activity.
3. Example 3: Endotracheal
  Prefix: “endo-” = within
  Root: “trache-” = trachea or windpipe
  Suffix: “-al” = pertaining to
  Endotracheal = pertaining to within the trachea
Combining Vowels: Often, an “o” (or sometimes an “i”) is added to make the term easier to pronounce. For example, “cardi” + “logy” becomes cardiology (the study of the heart).

No Prefix Needed: Not every term requires a prefix; some just use a root and suffix (e.g., “arthritis”).

By practicing with these components, you’ll start to recognize and even create medical terms that describe various body parts, conditions, and procedures.

4.2 Tips to Help you Understand Medical Terminology

Break Down the Words Into Parts

Medical terms often have three main parts: prefix, root, and suffix. Each part has a meaning, and together they form the whole term.
- Prefix: Comes at the beginning and often tells you something about location, time, or amount. For example, “hyper-” means “above” or “excessive.”
- Root: The main part of the word, usually tells you what body part is involved. For example, “cardi-” means “heart.”
- Suffix: Comes at the end and tells you what’s happening, like the condition, disease, or procedure. For example, “-itis” means “inflammation.”So, if you see “carditis,” you know it refers to inflammation of the heart. “Cardi-” (heart) and “-itis” (inflammation) combine to give you “heart inflammation.”

Look for Clues in Everyday Words

Some medical terms have similar roots or parts to words we already know. For example, “therm-” relates to temperature, just like “thermometer,” and “gastro-” relates to the stomach, like in “gastronomy” (cooking). If you can spot these familiar parts, it can help you guess the term’s meaning.

Learn Common Prefixes and Suffixes

Many prefixes and suffixes show up in different medical words. Learning a few can give you an edge:
- Prefixes: “hyper-” (over or too much), “hypo-” (under or too little), “brady-” (slow), “tachy-” (fast).
- Suffixes: “-itis” (inflammation), “-ectomy” (removal), “-ology” (study of), “-pathy” (disease or disorder).
For instance, “appendectomy” breaks down to “append-” (appendix) and “-ectomy” (removal), meaning “removal of the appendix.”

Practice with Real-World Examples

Try looking at words in common medical settings, like “dermatology” signs at clinics (skin study or treatment) or “phlebotomy” on a lab sign (cutting into or drawing blood). Over time, you’ll start to connect these terms to familiar experiences.

Use Resources for Quick Lookups

Don’t hesitate to use a medical dictionary or even a trusted online resource if a word is confusing. Many medical dictionaries are designed to be user-friendly, explaining terms in plain language and giving you both the technical and the everyday meanings.

With some practice, these terms start to look a lot more approachable. The goal isn’t exactly memorization but understanding each part, so you can make an educated guess about what a term means.

4.3 Terms You Should Know

What follows are some of the most common root words, prefixes, suffixes, and directional terms. You should study and understand these as a medical responder.

Root Words

The roots of medical terminology often come from Latin or Greek origins, which is why many terms may sound unfamiliar to beginners. However, knowing some basic roots can give insight into a wide array of terms. For example, “hepat” refers to the liver, and “derm” relates to the skin. Once you familiarize yourself with these common roots, recognizing them in different contexts becomes easier. Additionally, many terms are built from combinations of these roots and affixes (prefixes and suffixes), creating a flexible system for describing medical conditions, anatomy, or procedures.

Acou-: Refers to sound or hearing. Used in terms like acoustic, which pertains to sound properties, often relevant in diagnosing hearing disorders or discussing sound perception.
Aorta: The main artery leaving the heart’s left ventricle, delivering oxygenated blood to the body. It is the largest artery and is essential in maintaining blood flow and pressure across major organs.
Aqua-: Means water. Seen in terms like aqueous, describing water-based solutions or fluids, often used to describe bodily fluids in different medical contexts (e.g., aqueous humor in the eye).
Asphyxia: A condition of oxygen deprivation or carbon dioxide buildup in the body, leading to unconsciousness or death. It’s pertinent to respiratory failure, obstructed airways, or during drowning.
Asthen-: Implies weakness, particularly of muscles. It appears in terms like myasthenia, a condition causing muscular weakness due to nerve transmission issues.
Audi-: Related to hearing. Auditory refers to the sense or organs of hearing, often used in diagnosing auditory system disorders or conditions affecting hearing ability.
Bronch-: Refers to the bronchi, the large air passages leading to the lungs from the trachea, important in understanding respiratory issues, especially in conditions like bronchitis or asthma.
Bucc-: Relates to the cheek. Used in terms like buccal, which describes something associated with the cheek area, commonly used in dentistry or oral health contexts.
Bursa: A fluid-filled sac that reduces friction between tissues like bone and tendon, commonly found in joints. Bursitis, an inflammation of the bursa, is a frequent issue in joint pain and arthritis.
Callus: Refers to a thickened area of skin due to repeated friction. Also describes the connective tissue that forms as part of bone healing after a fracture.
Carcin-: Denotes cancer. Seen in words like carcinogen, referring to substances that can cause cancer, highlighting its role in pathology and oncology.
Carotid: Major arteries in the neck that supply blood to the brain, neck, and face. They are crucial in diagnosing conditions like carotid artery disease, which can lead to strokes.
Carpus: The anatomical term for the wrist bones, essential in orthopedic and joint-related studies, especially in diagnosing fractures or carpal tunnel syndrome.
Cent-: Means hundred or one-hundredth, as in centimeter (one-hundredth of a meter). Often used in measurements within the metric system in clinical settings.
Digit: Refers to fingers or toes. Digital examination techniques are important in physical assessments, and digital injuries or deformities are common areas of study in orthopedics.
Flex-: Means to bend, commonly used in terms like flexor, muscles that bend a joint, important in movement and understanding musculoskeletal mechanics.
Foramen: An opening or hole in bones through which nerves or blood vessels pass, such as the foramen magnum at the skull’s base.
Fract-: Implies breaking, especially of bones, as seen in fracture, the term for a broken bone.
Gest-: Relates to carrying or producing, as seen in gestation (carrying a pregnancy) or congestion (a buildup or accumulation of fluids in the body).
-gram: Something written or recorded, like an electrocardiogram (ECG), a record of heart activity.
Graph-: Means to write or record, as in graphology (the study of writing), or radiograph (an X-ray image).
Humerus: The upper arm bone, vital in discussions of fractures, dislocations, or muscular attachments.
Idi-: Separate or distinct. Seen in terms like idiopathic, meaning a disease with no identifiable cause.
Iod(o)-: Pertains to iodine, a chemical element necessary for thyroid function, often discussed in endocrinology.
Lact-: Means milk, as in lactation, the process of producing milk, relevant in maternal health and nutrition.
Palpate: To examine by touch. A key diagnostic method in physical exams to detect lumps, tenderness, or other abnormalities.
Ped-: Relates to children (as in pediatrics) or the foot (as in pedal), important to child healthcare and anatomy studies.
Phot-: Refers to light. In phototherapy, light is used to treat conditions like jaundice or seasonal affective disorder.
Pleur-: Refers to the side or ribs, as in pleura, the membrane surrounding the lungs, relevant in respiratory conditions like pleurisy.
Pod-: Means foot, seen in podiatry, the study and treatment of foot conditions.
Radius: The forearm bone on the thumb side, and also a line from a circle’s center to the edge. Radius fractures are common in trauma cases.
Ren-: Pertains to the kidney, as in renal, describing kidney functions and conditions.
Retina: The light-sensitive layer at the back of the eye, central to vision, frequently discussed in ophthalmology.
Sepsis: A potentially life-threatening condition involving toxins or microorganisms in the blood, often resulting from infection.
Sept-: A wall or divider, like the septum between the nostrils.
Serum: The clear fluid portion of blood after clotting, used in various diagnostic blood tests.
Sinus: A cavity or channel, often in the skull, relevant to sinus infections or sinusitis.
Stature: Height, often measured in assessments of growth and development.
Stern(o)-: Relates to the sternum (the breastbone), vital in understanding chest anatomy and injuries.
Stoma: A small opening or mouth, often created surgically to allow passage of body waste (e.g., colostomy).
Toxic: Refers to anything poisonous or harmful, central to toxicology.
Vertigo: A sensation of spinning or dizziness, often associated with balance issues.
Viscer-: Refers to internal organs, as in visceral, relating to deep organ structures within the body.
Viscous: Describes thickness or stickiness, such as with blood, which is important in understanding blood flow and clotting

4.4 Medical Prefixes

Prefixes in medical terms provide additional details, such as location, quantity, or time. For example, “hypo-” means under or below, while “hyper-” refers to above or excessive. Understanding how these prefixes modify the meaning of the root word can help clarify terms. For instance, “hypoglycemia” (“hypo-” meaning below, “glyc-” referring to sugar) describes a condition of low blood sugar, whereas “hyperglycemia” refers to high blood sugar. This consistency allows medical professionals to quickly interpret and respond to specific conditions without needing extensive definitions.

a-: Without, lack of.

Used to describe the absence of something, typically referring to a lack of a particular condition or feature.
Example: Aseptic – without infection.

ante-: Before, forward.

Refers to something that occurs before a specific event, usually in a time-related context.
Example: Antenatal – before birth.

arteri(o)-: Artery.

Refers to conditions or structures related to arteries, the blood vessels that carry blood from the heart to the body.
Example: Arteriogram – imaging of an artery.

auto-: Self.

Describes something that acts on itself or originates within the same system.
Example: Autoimmune – the immune system attacking the body’s own tissues.

bi-: Two.

Indicates the presence of two or something affecting both sides of a structure or condition.
Example: Bilateral – affecting both sides.

brady-: Slow.

Refers to something that is slower than normal, often used in relation to physiological functions.
Example: Bradycardia – slow heart rate.

cardi(o)-: Pertaining to the heart.

Describes anything related to the heart, including conditions, anatomy, and treatments.
Example: Cardiology – the study of the heart.

cephal(o)-: Pertaining to the head.

Refers to conditions or structures involving the head.
Example: Cephalalgia – headache.

cerebr(o)-: Pertaining to the cerebrum, a part of the brain.

Describes anything related to the cerebrum, the largest part of the brain, often associated with higher brain functions.
Example: Cerebrovascular – relating to the blood vessels of the brain.

cervic(o)-: Pertaining to the neck or uterine cervix.

Used for terms involving either the neck or the uterine cervix, depending on the context.
Example: Cervical – relating to the neck or the cervical region of the spine.

chemo-: Chemical.

Refers to chemical substances or processes, especially in medical treatments.
Example: Chemotherapy – treatment using chemicals.

circum-: Around, about.

Indicates something encircling or surrounding a particular area.
Example: Circumoral – around the mouth.

contra-: Against, opposite.

Describes opposition or resistance to a condition or treatment.
Example: Contraindication – a condition that works against a treatment.

cranio-: Skull.

Refers to the skull or cranium.
Example: Craniotomy – surgical opening of the skull.

cyan(o)-: Blue.

Typically used to describe conditions related to a bluish hue of tissues, often due to poor oxygenation.
Example: Cyanosis – a bluish discoloration of the skin due to lack of oxygen.

dermat(o)-: Pertaining to the skin.

Refers to anything related to the skin, including conditions and treatments.
Example: Dermatitis – inflammation of the skin.

electro-: Pertaining to electricity.

Describes anything related to electrical activity, often in the context of bodily functions.
Example: Electrocardiogram (ECG) – a test that measures electrical activity of the heart.

enter(o)-: Pertaining to the intestines.

Refers to conditions or anatomy involving the intestines, particularly the small intestine.
Example: Enteritis – inflammation of the intestines.

erythr(o)-: Pertaining to anything red or to erythrocytes (red blood cells).

Used to describe conditions or elements that are red in color or related to red blood cells.
Example: Erythrocyte – red blood cell.

gastr(o)-: Pertaining to the stomach.

Refers to anything related to the stomach.
Example: Gastritis – inflammation of the stomach lining.

gynec(o)-: Pertaining to females or the female reproductive organs.

Describes anything involving the female reproductive system or women’s health.
Example: Gynecology – the study of female reproductive health.

glyc(o)-: Sugar.

Refers to sugar, often in the context of glucose in the blood.
Example: Glycemia – the presence of glucose (sugar) in the blood.

hemat(o)-: Pertaining to blood.

Refers to conditions, functions, or studies related to blood.
Example: Hematology – the study of blood.

hepat(o)-: Pertaining to the liver.

Used for terms related to the liver, including diseases and anatomical studies.
Example: Hepatitis – inflammation of the liver.

hyster(o)-: Pertaining to the uterus.

Refers to anything involving the uterus.
Example: Hysterectomy – surgical removal of the uterus.

hemi-: Half.

Indicates something affecting one half or side.
Example: Hemiplegia – paralysis of one side of the body.

hydr(o)-: Water.

Refers to water or fluids, often in the context of fluid balance or treatment involving fluids.
Example: Hydration – maintaining adequate fluid in the body.

hyper-: Over, excessive.

Refers to something that is above normal or excessive.
Example: Hypertension – abnormally high blood pressure.

hypo-: Under, deficient.

Indicates something that is below normal or deficient.
Example: Hypoglycemia – low blood sugar.

infra-: Below.

Refers to something positioned below a specific anatomical structure.
Example: Infrapatellar – below the kneecap.

inter-: Between.

Indicates something located between two structures.
Example: Intercostal – between the ribs.

intra-: Within.

Refers to something occurring inside or within a specific structure.
Example: Intravenous – within a vein.

iso-: Equal.

Describes something that is equal or balanced in relation to another factor.
Example: Isotonic – having equal tension or pressure.

leuk(o)-: Pertaining to anything white or to leukocytes (white blood cells).

Describes things that are white in appearance or relate to white blood cells, a key component of the immune system.
Example: Leukocyte – white blood cell.

latero-: Side.

Refers to something located on or moving toward the side of the body.
Example: Lateral – situated on the side.

mening(o)-: Pertaining to a membrane, particularly the meninges.

Refers to the membranes that cover the brain and spinal cord, often in the context of diseases affecting them.
Example: Meningitis – inflammation of the meninges.

macro-: Large.

Indicates something large in size or scale.
Example: Macrophage – a large white blood cell that engulfs and digests pathogens.

mal-: Bad or abnormal.

Refers to something that is bad, inadequate, or abnormal.
Example: Malnutrition – poor or inadequate nutrition.

medi-: Middle.

Describes something located in the middle or center.
Example: Mediastinum – the central area between the lungs.

mega-: Large.

Refers to something that is large, often abnormally so.
Example: Megacolon – an abnormally large colon.

melan-: Black.

Refers to something black or dark, often related to pigmentation.
Example: Melanoma – a type of skin cancer involving pigment-producing cells.

meso-: Middle.

Indicates a middle position, typically within layers of tissue or structures.
Example: Mesoderm – the middle layer of embryonic tissue.

micro-: Small.

Refers to something small or minute in size.
Example: Microscope – an instrument used to see small objects.

mort(o)-: Death.

Related to death or dying.
Example: Postmortem – after death.

nas(o)-: Pertaining to the nose.

Used for terms involving the nose, typically in medical procedures or conditions.
Example: Nasogastric tube – a tube inserted through the nose and into the stomach.

nephr(o)-: Pertaining to the kidney.

Refers to anything related to kidney function, disease, or anatomy.
Example: Nephrology – the study of the kidneys.

neur(o)-: Pertaining to a nerve or the nervous system.

Describes anything related to nerves or the nervous system.
Example: Neurology – the study of the nervous system.

noct-: Night.

Refers to something that occurs during the night.
Example: Nocturia – frequent urination at night.

onco-: Pertaining to cancer, tumor.

Refers to the formation, study, or treatment of tumors and cancers.
Example: Oncology – the study of tumors and cancer.

oro-: Pertaining to the mouth.

Used for terms involving the mouth and its functions or conditions.
Example: Oropharyngeal – relating to the mouth and pharynx.

oste(o)-: Pertaining to the bone.

Refers to anything related to bones, including diseases and treatments.
Example: Osteoporosis – a condition characterized by weakened bones.

para-: By the side of.

Indicates something alongside or adjacent to a structure.
Example: Parathyroid – glands located beside the thyroid.

peri-: Around.

Refers to something around or encircling a structure.
Example: Pericardium – the sac surrounding the heart.

pseud(o)-: False.

Describes something that is not real or genuine, often appearing to be true but not.
Example: Pseudocyesis – false pregnancy.

psych(o)-: Pertaining to the mind.

Describes conditions or studies related to mental processes and behavior.
Example: Psychology – the study of the mind and behavior.

pulm(o)-: Pertaining to the lung.

Refers to anything involving the lungs.
Example: Pulmonology – the study of lung conditions.

path(o)-: Pertaining to disease.

Describes conditions related to diseases or their processes.
Example: Pathology – the study of disease.

phag(o)-: Pertaining to eating, ingesting, or engulfing.

Refers to the process of eating or engulfing, typically used in cellular or immune functions.
Example: Phagocytosis – the process of a cell engulfing particles.

pharyng(o)-: Pertaining to the throat or pharynx.

Describes conditions or structures related to the throat or pharynx.
Example: Pharyngitis – inflammation of the pharynx or throat.

pneum(o)-: Pertaining to respiration, the lungs, or air.

Refers to anything related to breathing, the lungs, or the presence of air.
Example: Pneumonia – infection of the lungs.

retr(o)-: Backward or behind.

Indicates a position or motion that is behind or backward.
Example: Retrograde – moving backward or reversing.

super-: Above, excessive, or more than normal.

Describes something that is above, over, or in excess.
Example: Superficial – situated or occurring on the surface.

supra-: Above.

Refers to something located above or higher than a specific anatomical structure.
Example: Suprapubic – above the pubic bone.

tachy-: Fast.

Describes a rapid or accelerated condition, often related to physiological functions.
Example: Tachycardia – abnormally fast heart rate.

trans-: Through, across.

Indicates movement through or across something, often a tissue or structure.
Example: Transdermal – through the skin.

therm-: Pertaining to temperature.

Describes anything related to heat or temperature regulation.
Example: Thermometer – an instrument used to measure temperature.

thorac(o)-: Pertaining to the chest.

Refers to conditions, treatments, or anatomy involving the chest cavity.
Example: Thoracotomy – surgical incision into the chest wall.

vas(o)-: Vessel.

Refers to blood vessels or any tube-like structure that carries fluids within the body.
Example: Vasoconstriction – narrowing of blood vessels.

4.5 Medical Suffixes

Suffixes often indicate the procedure, condition, or disease being referred to in medical terminology. For example, “-itis” denotes inflammation, as seen in terms like “arthritis” (inflammation of the joints). Similarly, “-ectomy” refers to the removal of something, such as in “appendectomy” (removal of the appendix). Recognizing these common suffixes helps healthcare providers to communicate efficiently and accurately, as well as aiding students in grasping the meaning of unfamiliar words.

-centesis: Pertaining to a procedure in which an organ or body cavity is punctured, often to drain excess fluid or obtain a sample for analysis.

Commonly used in procedures where a fluid sample is needed or excess fluid must be drained to relieve pressure.
Example: Thoracentesis – puncture of the chest cavity to remove fluid.

-ectomy: Surgical removal of.

Refers to the complete removal of a part or organ, typically to treat or prevent disease.
Example: Appendectomy – removal of the appendix.

-emia: Pertaining to the presence of a substance in the blood.

Indicates the presence, abundance, or deficiency of a specific substance in the bloodstream.
Example: Anemia – a deficiency of red blood cells in the blood.

-gram: Record.

Refers to a written or digital record, often of physiological data.
Example: Electrocardiogram(ECG) – a recording of the heart’s electrical activity.

-graph: A record or the instrument used to create the record.

Used to describe both the record itself and the equipment that captures the data.
Example: Mammograph – an instrument that records images of breast tissue.

-itis: Inflammation.

Denotes inflammation, typically due to infection, injury, or autoimmune processes.
Example: Arthritis – inflammation of the joints.

-lysis: Decline, disintegration, or destruction.

Often indicates the breakdown of cells, tissues, or compounds, either naturally or due to medical interventions.
Example: Hemolysis – destruction of red blood cells.

-megaly: Enlargement of.

Describes abnormal enlargement, typically due to disease or overuse.
Example: Cardiomegaly – enlargement of the heart.

-ology: Science of.

Indicates a branch of scientific study, often focused on a specific body system or condition.
Example: Neurology – the science of the nervous system.

-osis: Pertaining to a disease process.

Typically refers to a chronic, progressive disease process affecting tissues or organs.
Example: Cirrhosis – disease process leading to liver scarring.

-ostomy: Surgical creation of an opening or hole.

Refers to the creation of a permanent or semi-permanent opening, often to allow bodily functions to bypass damaged areas.
Example: Colostomy – creating an opening in the colon for waste removal.

-otomy: Surgical incision.

Involves cutting into an area of the body for access, examination, or treatment.
Example: Laparotomy – surgical incision into the abdomen.

-pathy: Disease or a system for treating disease.

Refers to diseases or conditions affecting a particular area, or to treatment systems like osteopathy.
Example: Neuropathy – disease of the nerves.

-phagia: Pertaining to eating or swallowing.

Indicates conditions affecting the ability to eat or swallow.
Example: Dysphagia – difficulty swallowing.

-phasia: Pertaining to speech.

Describes speech disorders, often neurological in origin.
Example: Aphasia – loss of ability to speak or understand speech.

-phobia: Pertaining to an irrational fear.

Refers to intense and often irrational fears of specific objects or situations.
Example: Claustrophobia – irrational fear of confined spaces.

-plasty: Plastic surgery.

Involves the reconstruction or modification of body structures.
Example: Rhinoplasty – plastic surgery of the nose.

-plegia: Paralysis.

Describes paralysis affecting specific body areas, often due to nerve or brain injury.
Example: Hemiplegia – paralysis of one side of the body.

-pnea: Pertaining to breathing.

Refers to conditions affecting the respiratory rate, rhythm, or volume.
Example: Apnea – temporary cessation of breathing.

-rrhage: Abnormal or excessive flow or discharge.

Indicates a sudden and excessive outflow, often involving blood.
Example: Hemorrhage – excessive bleeding.

-rrhea: Flow or discharge.

Refers to a steady or periodic discharge, usually from a body orifice.
Example: Diarrhea – frequent discharge of watery stool.

-scope: Instrument for examination.

Used for instruments that allow visual examination of internal structures.
Example: Endoscope – instrument used to examine the interior of a body cavity.

-scopy: Examination with an instrument.

Refers to procedures using a scope to visualize and diagnose conditions in various parts of the body.
Example: Colonoscopy – examination of the colon.

4.6 Directional Terms

Knowing directional terms in medical terminology ensures precision in communication, especially when describing the location of injuries, conditions, or procedures. These terms provide a universal language that eliminates ambiguity and helps healthcare providers communicate with accuracy and efficiency. For instance, using terms like “proximal,” “distal,” or “anterior” allows professionals across different specialties to understand exactly where an issue is located without lengthy explanations.

Superior – toward the head end of the body.

Used to describe a part of the body that is closer to the head than another part. For instance, the chest is superior to the abdomen. Think of this as moving “upward” from the feet toward the head.

Inferior – away from the head.

Refers to something farther from the head or closer to the feet. The knees, for example, are inferior to the hips. This term helps orient structures along the head-to-toe axis.

Anterior – front.

Indicates the front-facing side of the body. The chest, abdomen, and face are considered anterior structures. This term is interchangeable with “ventral” in human anatomy.

Posterior – back.

Describes structures toward the back of the body, like the spine or buttocks. Posterior is often synonymous with “dorsal,” referring to the back side.

Medial – toward the midline of the body.

This term describes something closer to the imaginary line running down the center of the body. The nose, for example, is medial to the eyes, as it is closer to the midline than the eyes.

Lateral – away from the midline of the body.

Refers to structures farther from the midline. The arms are lateral to the chest, meaning they are positioned on the sides, further from the body’s central axis.

Proximal – toward or nearest the trunk or the point of origin of a part.

Primarily used in reference to limbs, this term indicates closeness to the trunk of the body. The shoulder is proximal to the wrist, as it is closer to where the arm attaches to the body.

Distal – away from or farthest from the trunk or the point or origin of a part.

Also typically applied to limbs, distal indicates distance from the body’s main mass. The hand is distal to the elbow, meaning it is farther away from the point where the arm connects to the torso.

4.7 Introduction to Body Systems

The following are the body systems. These are important to know so you can better understand the processes of the body. As you learn medical terminology and understand how the body works, you come to realize the importance of knowing each system, how it works, and how they interact with one another to help the body function properly.

Skeletal system – framework of the body, includes bones. Here are some common medical terms related to the skeletal system.

Nervous system – network of nerves cells and fibers that transmit nerve impulses throughout the body. Here are some common medical terms related to the skeletal system.

Muscular system – aids in movement, blood flow, and other bodily functions. Here are some common medical terms related to the skeletal system.

Respiratory system – brings in oxygen and expels carbon dioxide. Here are some common medical terms related to the skeletal system.

Endocrine system – collection of glands that secrete hormones to be delivered to the body’s organs. Here are some common medical terms related to the skeletal system.

Immune system – body’s defense against bacteria, viruses, and other pathogens. Here are some common medical terms related to the skeletal system.

Cardiovascular/circulatory system – permits blood to circulate and transport nutrients, oxygen, carbon dioxide, hormones, and blood cells. Here are some common medical terms related to the skeletal system.

Urinary system – eliminates waste products from the body. Here are some common medical terms related to the skeletal system.

Integumentary system – protects the body from damage, loss of water, or abrasion from outside. Here are some common medical terms related to the skeletal system.

Reproductive system – combination of bodily organs and tissues used in the process of producing offspring. Here are some common medical terms related to the skeletal system.

Digestive system – breaks down food, extracts nutrients into the bloodstream, and excretes waste. Here are some common medical terms related to the skeletal system.

Additional Resources to Help You Learn

Supplementary YouTube videos:

medical terminology introduction

Basic Medical Terminology – Language of Medicine, Chapter 1

Supplementary Websites with interactive content:

Medline Plus – Understanding Medical Words Tutorial

InterActive Medical Terminology

Open Education Alberta’s The Language of Medical Terminology Review Exercises

Quizlet – Medical Terminology Chapter 1: Introduction to Medical Terminology Learning Exercise

References

Betts, J. G., Young, K. A., Wise, J. A., Johnson, E., Poe, B., Kruse, D. H., Korol, O., Johnson, J. E., Womble, M., & DeSaix, P. (2022). Anatomy and physiology 2e. OpenStax. https://openstax.org/books/anatomy-and-physiology-2e/pages/1-introduction

Ernstmeyer, K., & Christman, E. (Eds.). (2024). Medical terminology 2e. Open RN | WisTech Open. https://wtcs.pressbooks.pub/medterm/

Videos:

License

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