Scientific/Medical Terminology - Module 1 Prefixes

ec- (ex- before a vowel)

Out of, away from

ecto- (ect- often before a vowel)

Outside of

en- (em- before b, m, and p)

In, into, within

endo-, ento- (end-, ent- before a vowel)

Within

epi- (ep- before a vowel or h)

Upon, over, above

exo-

Outside, from the outside, toward the outside

a- (an- before a vowel or h)

Not, without, lacking, deficient

anti- (ant- before a vowel or h; hyphenated before i )

Against, opposed to, preventing, relieving

di- (rarely dis-)

Two, twice, double

dys-

Difficult, painful, defective, abnormal

hemi-

Half, partial; (often) one side of the body

hyper-

Over, above, excessive, beyond normal

hypo- (hyp- before a vowel or h)

Under, deficient, below normal

mono- (mon- before a vowel or h)

One, single

Peri-

Around, surrounding

Syn- (sym - before b, p , and m ; the n assimilates or is dropped before s )

Together, with, joined