# Basic Concepts of Medical Terminology

# "Medical terminology is the professional language of those who are directly or indirectly engaged in the art of healing." (Frenay and Mahoney, 1998) Most medical terms have Greek or Latin origins, though some are derived from modern languages, particularly German, French, and English. In general, terms dealing with diagnosis and surgery have Greek origins, whereas anatomical terms have Latin origins. An understanding of the structure of medical terms, and an ability to break down a medical term into its parts helps you get the most out of using a medical dictionary, and makes dealing with medical terminology less challenging than it first appears.

Medical terms are formed from word *roots*, *prefixes*, *suffixes*, and
*combining vowels/forms*, defined below:

**Root** -- the foundation of the word, it can be combined with a prefix
or suffix

**Prefix** -- placed before the root to modify its meaning

**Suffix** -- placed after the root to modify and give essential meaning
to the root; forms a noun, verb, or adjective

**Combining form** -- root with a **combining vowel** attached (e.g.
*lip/o-*); ***o*** is the most common combining vowel

In "decoding" medical terms, it is best to look first at the meaning of
the suffix, then at the meaning of the root or root and prefix.

Example: **hyperlipoproteinemia**

hyper- (prefix) = excessive

lip (root) = fat

o (vowel used to create a combining form, lipo-)

protein (root) = protein

-emia (suffix) = blood condition

Hyperlipoproteinemia is a blood condition, characterized by an excessive
amount of fat and protein.

Example: **pericarditis**

peri- (prefix) = around

cardi (root) = heart

-itis (suffix) = inflammation

Pericarditis literally means "inflammation around the heart" but the
dictionary states that this terms means inflammation of the pericardium
(-ium is a suffix meaning tissue), the sac that encloses the heart.

Various medical terms refer to divisions of the body, body position and
direction, planes of the body, and body cavities. Examples of these are:
*epigastric region* and *lower right quadrant* of the abdomen; *sacral
region* of the back; *superficial* position; *efferent* direction;
*horizontal* plane; and *frontal sinus*. It may be helpful to
familiarize yourself with some of these terms.

**Using the Dictionary**

When the exact word you need a definition for is not in the dictionary,
look up the root word. Medical dictionaries use sub-entries heavily. You
may find the exact word you are looking for listed under its root.

> Below is part of the entry for the word "*Kidney*" in ***Dorland's
> Illustrated Medical Dictionary***. Note the sub-entries.

**Kidney** (kid΄ne) \[L. *ren*; Gr. *nephros*\] \[MeSH: Kidney\] either
of the two

organs in the lumbar region that filter the blood.... The kidney
consists

of a *cortex* and a *medulla*.

**abdominal k.,** an ectopic kidney situated above the iliac crest with

the hilus adjacent to the second lumbar vertebra.

**flea-bitten k.,** a kidney which has small, randomly scattered

petechiae on its surface, sometimes seen in bacterial endocarditis.

If the exact word you were looking for isn't a sub-entry, look up the
word's prefixes and suffixes. Common medical prefixes and suffixes will
have main entries.

**Practice Exercises**

[Find the meaning of the word parts and words below:]{.underline}

+---+---------------+---------------------------------------------------+
|   |               | **[Definition]{.underline}**                      |
+---+---------------+---------------------------------------------------+
| * | **            | thorac-                                           |
| * | thoracotomy** |                                                   |
| 1 |               | -tomy                                             |
| * |               |                                                   |
| * |               |                                                   |
+---+---------------+---------------------------------------------------+
|   | *             | dermat-                                           |
|   | *dermatitis** |                                                   |
|   |               | -itis                                             |
+---+---------------+---------------------------------------------------+
| * | *             | gastr-                                            |
| * | *gastralgia** |                                                   |
| 3 |               | -algia                                            |
| * |               |                                                   |
| * |               |                                                   |
+---+---------------+---------------------------------------------------+

Medical Terminology: Prefixes

+-----------------------+-----------------------+-----------------------+
| ###### Prefix         | ###### Definition     | ###### Example        |
+-----------------------+-----------------------+-----------------------+
| a-, an-               | without; lacking      | > aphasia - without   |
|                       |                       | > speech              |
|                       |                       | >                     |
|                       |                       | > anemia - lack of    |
|                       |                       | > blood               |
+-----------------------+-----------------------+-----------------------+
| ab-                   | away from             | > abductor - leading  |
|                       |                       | > away from           |
+-----------------------+-----------------------+-----------------------+
| ad-                   | toward; near          | > adductor- leading   |
|                       |                       | > toward              |
|                       |                       | >                     |
|                       |                       | > adrenal - near the  |
|                       |                       | > kidney              |
+-----------------------+-----------------------+-----------------------+
| anti-/contra-         | against               | > anticoagulant -     |
|                       |                       | > prevent blood       |
|                       |                       | > clotting            |
|                       |                       | >                     |
|                       |                       | > contraception -     |
|                       |                       | > prevent             |
|                       |                       | > co                  |
|                       |                       | nception/impregnation |
+-----------------------+-----------------------+-----------------------+
| ect-, ecto-, exo-     | outer; outside        | > ectoderm - outer    |
|                       |                       | > skin                |
+-----------------------+-----------------------+-----------------------+
| end-, endo-, ent      | within; inner         | > endocranial -       |
|                       |                       | > within the cranium  |
|                       |                       | >                     |
|                       |                       | > endodontium -       |
|                       |                       | > dental pulp         |
+-----------------------+-----------------------+-----------------------+
| hyper                 | above, beyond,        | > hyperglycemia -     |
|                       | excessive             | > high glucose        |
|                       |                       | >                     |
|                       |                       | > hypertension - high |
|                       |                       | > blood pressure      |
+-----------------------+-----------------------+-----------------------+
| hyp-, hypo-           | under, deficient      | > hypothermia - low   |
|                       |                       | > body temperature    |
|                       |                       | >                     |
|                       |                       | > hypothyroidism -    |
|                       |                       | > thyroid deficiency  |
+-----------------------+-----------------------+-----------------------+
| infra-                | beneath; below        | > infraorbital -      |
|                       |                       | > beneath the eye     |
+-----------------------+-----------------------+-----------------------+
| inter-                | between               | > intercostal -       |
|                       |                       | > between the rib     |
+-----------------------+-----------------------+-----------------------+
| intra-                | within                | > intravenous -       |
|                       |                       | > within a vein       |
+-----------------------+-----------------------+-----------------------+
| neo-                  | new                   | > neonate - newly     |
|                       |                       | > born                |
+-----------------------+-----------------------+-----------------------+
| peri-                 | around                | > periodontal -       |
|                       |                       | > around the tooth    |
|                       |                       | >                     |
|                       |                       | > periosteum - around |
|                       |                       | > bone                |
+-----------------------+-----------------------+-----------------------+
| poly-                 | many, excessive       | > polycystic - many   |
|                       |                       | > cysts               |
|                       |                       | >                     |
|                       |                       | > polydipsia -        |
|                       |                       | > excessive thirst    |
+-----------------------+-----------------------+-----------------------+
| sub-                  | under                 | > subcutaneous -      |
|                       |                       | > under the skin      |
|                       |                       | >                     |
|                       |                       | > sublingual -        |
|                       |                       | > beneath the tongue  |
+-----------------------+-----------------------+-----------------------+

## 

Medical Terminology: Suffixes

+-----------------------+-----------------------+-----------------------+
| ###### Suffix         | ###### Definition     | ###### Example        |
+-----------------------+-----------------------+-----------------------+
| -algia, -dynia        | pain                  | > neuralgia - pain in |
|                       |                       | > nerves              |
+-----------------------+-----------------------+-----------------------+
| -centesis             | surgical puncture to  | > amniocentesis -     |
|                       | remove fluid          | > amniotic fluid      |
+-----------------------+-----------------------+-----------------------+
| -ectomy               | cut out, excision     | > appendectomy -      |
|                       |                       | > removal of the      |
|                       |                       | > appendix            |
+-----------------------+-----------------------+-----------------------+
| -emia                 | blood condition       | > anemia - low/lack   |
|                       |                       | > of red blood cells  |
|                       |                       | >                     |
|                       |                       | > leukemia -          |
|                       |                       | > malignant blood     |
|                       |                       | > disease             |
+-----------------------+-----------------------+-----------------------+
| -esis -ity            | state or condition    | > anesthesia - loss   |
|                       |                       | > of sensation        |
| -iasis -ia            |                       | >                     |
|                       |                       | > psoriasis - skin    |
| -osis -y              |                       | > condition           |
|                       |                       | >                     |
|                       |                       | > scoliosis - spine   |
|                       |                       | > curvature           |
+-----------------------+-----------------------+-----------------------+
| -gram, -graphy        | recording, written    | > mammogram - x-ray   |
|                       |                       | > of breast           |
|                       |                       | >                     |
|                       |                       | > cardiography -      |
|                       |                       | > record of physical  |
|                       |                       | > or functional       |
|                       |                       | > aspect of the heart |
+-----------------------+-----------------------+-----------------------+
| -ites, -itis          | inflammation          | > carditis -          |
|                       |                       | > inflammation of the |
|                       |                       | > heart               |
+-----------------------+-----------------------+-----------------------+
| -oma                  | tumor                 | lymphoma - lymph      |
|                       |                       | tissue                |
|                       |                       |                       |
|                       |                       | melanoma - tumor of   |
|                       |                       | pigment tissue        |
+-----------------------+-----------------------+-----------------------+
| -penia                | deficiency, lack of   | > glycopenia - sugar  |
|                       |                       | > deficiency in       |
|                       |                       | > tissues             |
+-----------------------+-----------------------+-----------------------+
| -phagia, phagy        | eating, devouring     | > tachyphagia -       |
|                       |                       | > eating fast         |
+-----------------------+-----------------------+-----------------------+
| -plasty               | surgical shaping      | > genioplasty - chin  |
|                       |                       | >                     |
|                       |                       | > rhinoplasty - nose  |
+-----------------------+-----------------------+-----------------------+
| -pnea                 | breathing             | > apnea - cessation   |
|                       |                       | > of breathing        |
|                       |                       | >                     |
|                       |                       | > dyspnea - labored   |
|                       |                       | > breathing           |
+-----------------------+-----------------------+-----------------------+
| -rrhaphy              | suture                | > gastrorrhaphy -     |
|                       |                       | > stomach             |
+-----------------------+-----------------------+-----------------------+
| -rrhea                | flow or discharge     | > rhinorrhea - nasal  |
+-----------------------+-----------------------+-----------------------+
| -stomy                | surgical opening      | > colostomy - into    |
|                       |                       | > the colon           |
|                       |                       | >                     |
|                       |                       | > tracheostomy - into |
|                       |                       | > the trachea         |
+-----------------------+-----------------------+-----------------------+
| -scopy                | to examine            | > cystoscopy -        |
|                       |                       | > bladder             |
|                       |                       | >                     |
|                       |                       | > cytoscoy - cells    |
+-----------------------+-----------------------+-----------------------+
| -tomy                 | cutting; incision     | > phlebotomy - into   |
|                       |                       | > the vein            |
+-----------------------+-----------------------+-----------------------+

Medical Terminology: Root Terms

+-----------------------+-----------------------+-----------------------+
| ###### Root           | ###### Definition     | ###### Example        |
+-----------------------+-----------------------+-----------------------+
| aden-                 | \[Gr.\] gland         | > adenoma             |
+-----------------------+-----------------------+-----------------------+
| blephar-              | \[Gr.\] eyelid        | > blepharoplasty      |
+-----------------------+-----------------------+-----------------------+
| cardi-                | \[Gr.\] heart         | > cardiography        |
+-----------------------+-----------------------+-----------------------+
| derm(at)-             | \[Gr.\] skin          | > dermatitis          |
+-----------------------+-----------------------+-----------------------+
| gastr-                | \[Gr.\] stomach       | > gastrostomy         |
+-----------------------+-----------------------+-----------------------+
| grav-                 | \[L.\] heavy          | > multigravida        |
+-----------------------+-----------------------+-----------------------+
| lingu-                | \[L.\] tongue         | > sublingual          |
+-----------------------+-----------------------+-----------------------+
| phob-                 | \[Gr.\] fear          | agoraphobia           |
+-----------------------+-----------------------+-----------------------+
| spirat-               | \[L.\] breathe        | > inspiratory         |
+-----------------------+-----------------------+-----------------------+
| thorac-               | \[Gr.\] chest         | > thoracoplasty       |
+-----------------------+-----------------------+-----------------------+

Medical Terminology: Other

Terms that reflect an aspect of a disease/condition:

anatomy -- science of the structure of the body; relation of its parts

physiology -- science dealing with the function of the body and its
parts

etiology -- what causes the disease

diagnosis -- determining what disease

therapy -- treatment of a disease

prognosis -- forecast of outcome of a disease

signs -- objective evidence of a disease; perceptible to the
practitioner

symptoms -- subjective sensations of the patient

Drug terminology:

brand name -- name used for a drug made by a particular company (e.g.
Snickers)

generic name -- name used for the drug, regardless of which company
makes it (e.g. candy bar)

indication -- condition for which you are taking the drug

contraindication -- condition that would preclude your taking the drug

precautions -- things you need to watch for when taking the drug

side effects -- effects other than the therapeutic effect of the drug

adverse reactions -- potentially harmful side effect

monograph -- information on a single drug

**Helpful Resources**

**Dictionaries**

DORLAND, NEWMAN W. Dorland\'s Illustrated Medical Dictionary. 29th

ed. Philadelphia, Saunders, 2000.

MAGALINI, SERGIO \[and others\]. Dictionary of Medical

Syndromes. 4th ed. Philadelphia, Lippincott Williams & Wilkins, 1997.

STEDMAN, THOMAS LATHROP. Stedman\'s Medical Dictionary. 27th ed.

Philadelphia, Lippincott Williams & Wilkins, 2000.

THOMAS, CLAYTON L., ed. Taber\'s Cyclopedic Medical Dictionary.

18th ed. Philadelphia, Davis, 1997.

**Terminology Tools**

FRENAY, AGNES CLARE, AND MAHONEY, ROSE MAUREEN. Understanding

Medical Terminology. 10th ed. New York, McGraw-Hill, 1998.

JONES, BETTY DAVIS. Delmar\'s Comprehensive Medical Terminology: A

Competency-Based Approach. Albany, NY, Delmar, 1999.

RICE, JANE. Medical Terminology with Human Anatomy. 4th ed. Upper

Saddle River, NJ, Prentice Hall Health, 1999.