List of Prefixes:
Learn New Words Faster

This list of prefixes, along with some common roots and suffixes, can help you recognize hundreds of words. Work with some of these 50 or so prefixes, or a few Latin roots, every day, and watch your English vocabulary take off!

On Thursday October 20, I'm giving a free webinar (twice) on Vocabulary Prep for the IELTS & TOEFL. It will include a demonstration on using context clues and word parts like prefixes and roots to figure out the meanings of words you don't know.

If you plan to study at an English-speaking university or to take the TOEFL or IELTS exam, (or want to recognize words from their roots and affixes), I think it will be helpful. There is more information here.

A few important notes about prefixes:

(Click here to go straight to the prefix list and save the explanations for later.)

1. There are often several prefixes with the same meaning, one from Latin and one from Greek, maybe even one from Anglo-Saxon (as with sub-, hypo-, and under-.) Often-- but not always-- they are used with a root from the same language. So we have ‘synthesis’ originally from Greek and ‘composite’ from Latin, both combining ‘with’+ the idea of setting down or placing something.

However, prefixes and roots don't have to match. 'Hyper,' (‘over’ or ‘excessive’ in Greek) can be combined with ‘active,’ from Latin, to make the common English word 'hyperactive.' See Common Greek and Latin Prefixes to compare these (and a few less common) synonym prefixes, in alphabetical order by English meanings.

How prefixes change meanings: a demonstration with 'press:' compress, depress, repress, suppress, etc.

2. Prefixes are commonly used to indicate size (macro, micro), quantity (mono, uni, bi, tri, quad, multi, poly), relationships (anti, contra, com, sym), position in time (ante, fore, pre, post) or space (circum, exo, inter, intra, peri, sub, trans, etc.), quality (eu, mal), or negation. (See Negative Prefix List for a more detailed discussion.)

3. Several prefixes have more than one form, usually because a different ending sounds better before certain letters. These include a- or an-, ad- (which often drops the ‘d’ and may double the consonant of the root word); co-, com-,or con-; il-, im-, in-, ir; pre-, pro-; sym-, syn-; and sometimes others, like sub-.

How prefixes change meanings: a demonstration with 'press:' compress, depress, repress, suppress, etc.

4. There are many more commonly-used prefixes. I tried to limit this list of prefixes to the most useful of all, so it would be short enough to learn easily. (You can find more complete lists on the Internet or in a good dictionary.)

After you read the definition and the examples for each prefix, try to think of another word or two made from it. For example: anonymous-- without a (known) name, abduct-- to “lead away” (move your arm or leg away from the body, or to kidnap someone from their home), adhesive, adjust or administer ...

Some prefix meanings will be obvious. Others will make more sense as you learn more words. See 50 Word Roots from Latin for prefixes combined with the Latin verb mittere, and then with other roots.

List of Prefixes: A-D

a-, an- without, not anesthetic, atheist
ab- away, from abject, abscess
ad-, a-, ac-, as- to, toward access, admit, assist
ante before antecedent, anterior
anti- against antibiotics, antioxidant
auto- self autoimmune, autonomous
ben- good benefit, benign
bi- two, both bifocals, bipolar
circum- around circumference, circumscribe
co-, com-, con- with companion, concurrent
contra-, counter- against contradict, counteract
de- not, from, down degenerate, depress
di-, dis- lack of, not, apart disadvantage, displacement

Prefixes E-M

eu- good, normal eugenics, eulogy
ex- out (of), former expose, extract
exo-, ecto-, extra-, extro- outside exoskeleton, extraordinary
fore- before foresee, foreshadow
hemi- half hemisphere
hyper above, excessive hyperactive, hypertension
hypo- under, insufficient hypodermic, hypothetical
il-, im-, in-, ir- in, into, not, against illegitimate, inadequate
inter- among. between interpose, intervene
intra- within intramural, intravenous
macro- large macrobiotic, macrocosm
mal- bad malfunction, malignant
micro- small microbe, microscope
mis- wrong misfortune, mistake
mono- one monolingual, monopoly
multi- many multiple, multitask

Prefixes: N-U

non- not, lacking nonfat, nonsense
ob-,o-, oc-, op- against, over, completely object, occur, omit, oppose
omni- all omnipotent, omnivorous
peri- around peripheral, periscope
poly- many polygamous, polygon
post- after postgraduate, postpone
pre- before precede, predict, prevent
pro- forward progress, promotion
quad- four quadriplegic, quadrangle
re- again, back reform, retain, regenerate
semi- half, partially semiannual, semiconscious
sub- under submarine, subtropical
super-, supra- above, excessive superlative, suprarenal
sym-, syn- with, together sympathy, synthetic
trans- across, beyond Transform, transportation
tri- three tricycle, triple
ultra- beyond. excessive ultraliberal, ultrasonic
un- not undeserved, unhappy
uni- one uniform, unilateral

This table, as well as information and practice on these prefixes, is also available as an inexpensive pdf for classes on Root, Prefix, and Suffix Worksheets. You can also get a similar version of just the prefix table and negative prefix list here. (Right-click to download.)

You can practice with prefixes at 7+ Common Prefixes, The Prefix 'Re', or Practice Negative Prefixes.

Word Families shows you how these prefixes change one word family (act), and 50 Latin Word Roots shows how they are used with many roots, as well as giving a complete demonstration with one. You might also like English Word Origins, List of Suffixes or Important Latin Roots.

Home> Roots, Prefixes, and Suffixes > List of Prefixes.

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