Introduction To Medical Terms

Medical terms are created by stringing word parts with specific meanings together to identify a body part, a disease, a procedure, etc.
Terms are created from four general word parts:
1. prefixes;
2. suffixes;
3. roots; and
4. combining vowels.
Roots are the main part of the word.
Prefixes are parts of words that go before the root.
Suffixes are parts of words that go after the root or roots.




Cardiovascular System

(the heart and blood vessels)
come from

the roots
cardi (heart)
and vas (vessel)

Prefixes and suffixes cannot stand alone; they must be combined with a root.
Prefixes and suffixes serve to expand or alter the meaning of a root.
A root is the foundation or subject of the word. It usually relates to the body or a body system.
Combining vowels are used sometimes to link word parts together.

For example, the rootcardi identifies the subject of the word as the heart.

Sometimes a medical term is just a root word with an ending that does not change or alter the root.

These endings include
-ac, -ic, -al, and -ous.
These endings simply relate to the root.
So, the word Cardiac means (or relates to) heart.

 Example: electrocardiogram, a record of the electrical activity of the heart

elecr- = elecric + cardi- = heart + -gram = tracing

Combining Vowels

Word parts are joined together with the combining vowel (o).

A combining vowel is usually used when the next linking word part begins with a consonant.

The most common combining vowel is O.

However, when the next word part begins with a vowel, or the preceding word part ends with a vowel, the combining vowel is usually dropped

electrocardiogram, the combining vowel between the root and the suffix was used even though the root word ended with a vowel. This represents an exception to the rule of not using the combining vowel, and may be effective when linking some root words together. Look at this example.

The prefix peri- means around or surrounding.

Cardi still refers to the heart.

The suffix -itis means inflammation.

When you link the prefix peri- with the root word cardi, even though the root begins with a consonant, no combining vowel is necessary.

Likewise, when you link the root word cardi with the suffix -itis, no combining vowel is necessary.

In fact, in this instance, one of the i's is dropped. Pericarditis.

Respiratory System


(the lungs and airways)
use the roots
pneum- (air or lung)
pulmon- (lung) or
bronch- (airway)




The Suffix

The suffix provides an ending that modifies and gives meaning to the root word.

Study the examples that follow
and notice how adding a different suffix
to the same root produces new words.


Example: tonsil
Tonsils are glands a the back of the throat.
they are part of the immune system.
 A condition (itis)  Tonsilitis
 To cut out (ectomy)  Tonsilectomy

More Roots and Suffixes
Example: necr-, root word meaning issue dead

Adding the suffix -osis (condition) creates necrosis (condition of issue dead)

necro- + -osis = necrosis. Note that one o is dropped when the two parts are combined

Adjective Suffixes


 Some suffixes have more than one meaning
Some multiple suffixes have a particular meaning.
For example, the adjective suffixes -ac, -al, -ar, -ary, -eal, -ic, -ous, and -ic mean
"pertaining to"

They are added to a root to make the adjective form of the word as in cephalic

(cephal- + -ic = cephalic,

meaning "pertaining to the head").



A prefix is a word part that comes before (pre- = before) the root and begins the term. Prefixes further modify the root or roots; they often give an indication of direction, time, or orientation.


 Example: prenatal

(pre- + natal), before birth

pre- = before + natal = birth


 Example: intra-abdominal (Intr- + abdomen/o + -al),

pertaining to within the abdomen

Intra- = within + abdomen/o = abdomen + -al = pertaining to

More than one root-
Additional Roots

Some medical terms contain more than one root. Study the meaning of each root.
As your vocabulary grows, you will quickly learn to identify the primary root word--if there is one.
Remember, some terms may contain several root words of equal importance to the term's definition.


 Example: electrocardiogram, a record of the electrical activity of the heart

elecr- = elecric + cardi- = heart + -gram = record
(root) (root) (suffix)

Example: tracheobronchitis, an inflammation of the trachea and lungs

trach- = trachea + bronch- = lungs + -itis = inflammation of
(root) (root) (suffix)


Combining Vowels and Forms

Adding a combining vowel to a root word creates a word part called a combining form.

Combining vowels make it easier to spell and pronounce medical terms.
They also serve as connectors for root words when more than one root is needed to form a term.
In addition, a combining vowel may be used to join a root word and a suffix.
The most frequency used combining vowel is o; the second most common is i.


 Example: abdominocenesis (abdomen/o + -cenesis),

the puncture of the abdomen for withdrawal of fluid

abdomen/o = abdomen +
= puncture for withdrawal of fluid


Tips to Remember
 TIP #1


Most medical terms contain two or more of these parts:
root(s) ­ the word's essential meaning; a term may have two roots
Prefix ­ added to the beginning of a root word to make it more specific
Suffix ­ added to the end of the root word for specificity
Linking or combining vowels ­ placed in between word parts to help with pronunciation
 TIP #2

The definitions of root words, prefixes and suffixes remain the same

when they are combined to produce different terms.

 Three examples:








TIP # 3.

 A. the root word for skin is derm.

Its combining forms are derma-, derma-, dermo-, and dermo- .
Look at some medical terms utilizing this root:

Dermatitis ­ Derma (root) and ­itis (suffix) inflammation - condition of inflamed skin.
Dermatology ­ Derma (root) and ­ology (suffix) branch of knowledge or science
B. Card is the root for heart.
Cardiovascular - means pertaining to the heart tand vessels.
Cardiocenesis ­ surgical puncture of the heart.
Cardiology ­ as in Example A above, the definition here is the study of the heart and its functions.
C. the root for blood is hem.
hemorrhage ­ the suffix ­rrhage means bursting forth; hemorrhage is the escape of blood from tissue.
hemostasis ­ adding the suffix ­stasis (a rest in a process) gives us the process by which bleeding is stopped.

Similarly, prefixes and suffixes are defined the same when combined wiht various roots.

They are never used alone, but further define root words.

    Common prefixes in medical terminology:
    Auto- = self; for example, autoimmune or autogenous
    Anti- = against; antisepsis or antibodies
    De- = dehydrate, defibrillate
    Re-= reverse, remove;
    Dys- = abnormal, difficult; dysuria
    Contra- = opposed; for example, contraception, contraindication
    Hyper- = above, excessive; hypertensive, hyperglycemia
    Surgical Suffixes
    -ectomy = surgical removal; appendectomy
    -plasty = surgical repair; angioplasy
    -stomy = creation of a new opening; colonostomy
    Procedures or Equipment
    -graph = recording instrument; electrocardiograph
    -scope = instrument to examine visually; endoscope
    -therapy = course of treatment; chemotherapy
    Pronunciation Tips
Medical Terms are often hard to pronounce, especially if you have never heard or seen ttthe word. Here are some helpful hints:
Pronounce "-es" at the end of a word as a separate syllable "-eez." Example: nares.
Pronounce "-i" at the end of a word to form a plural as "eye." Example: fasciculi.
Pronounce "pn" as an "n." Example: pneumothorax.
Routinely pronounce "ch" as a "k." Example: chronic.
 Study Guides (University of Minnesota)
 Click there to study or download a list ofthe most common prefixes, roots and suffixes.

Then practice combining medical terms at the same site by clicking on med_term_activities

Medical Term Activities with Roots, Suffixes and Prefixes

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