Recognize hundreds of English words with this list of prefixes (along with some common roots and suffixes.) Practice a few prefixes every day-- with a new root every week or two. Your English vocabulary will take off!
1. There are often several prefixes with the same meaning. One may come from Latin and one from Greek.
Sometimes there's also an Anglo-Saxon prefix. (See sub- and hypo-, along with '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. They both combine a prefix meaning ‘with’ and the idea of setting something down.
Prefixes and roots don't have to match. 'Hyper,' (‘over’ or ‘excessive’ in Greek) can be combined with ‘active,’ from Latin. They make the common English word 'hyperactive.'
See Common Greek and Latin Prefixes to compare these and other prefixes in alphabetical order by English meanings. (See also Greek Roots. Many words there can also be used as prefixes: bio-, photo-, tele-, etc.)
2. Prefixes are commonly used to indicate
3. Several prefixes have more than one form, usually because a different ending sounds better before certain letters. These include
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:
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 useful roots.
There are many other prefix examples on the pages mentioned below the prefix list.
|a-, an-||without, not||anesthetic, atheist|
|ab-||away, from||abject, abscess|
|ad-, a-, ac-, as-||to, toward||access, admit, assist|
|bi-||two, both||bifocals, bipolar|
|co-, com-, con-||with, together||companion, concurrent*|
|contra-, counter-||against||contradict, counteract|
|de-||down, undo, not||degenerate, depress|
|di-, dis-||lack of, not, apart||disadvantage, displacement|
|eu-||good, normal||eugenics, eulogy|
|ex- (or e-)||out (of), former||expose, extract|
|exo-, ecto-, extra-, extro-||outside||exoskeleton, extraordinary|
|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|
|non-||not, lacking||nonfat, nonsense|
|ob-,o-, oc-, op-||against, over, completely||object, occur, omit, oppose|
|over-||too much, general||overall, overdone, overview|
|pre-||before||precede, predict, prevent|
|re-||again, back||reform, retain, regenerate|
|semi-||half, partially||semiannual, semiconscious|
|sub-, sup-, sus-||under||submarine, subtropical|
|super-, supra-||above, excessive||superlative, suprarenal|
|sym-, syn-||with, together||sympathy, synthetic|
|trans-||across, beyond||Transform, transportation|
|ultra-||beyond. excessive||ultraliberal, ultrasonic|
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 from the student version of that page, just below the prefix packet.
You can practice with prefixes at 8+ Common Prefixes, The Prefix 'Re', or Practice Negative Prefixes. These pages also give you many examples of each prefix (including almost 50 prefix examples just on the Common Prefixes page).
The practice exercises show ways to use them in sentences.
The Negative Prefix List page doesn't have practice, but it gives an explanation of the differences between the prefixes and provides lots of examples.
You can find more complete explanations of the examples in the yellow box (& other words from those roots) on
(as well as several other practice pages linked from them.)
More examples of words with co-, com-, or con- on those pages: colleagues, commit, commotion, compelling, complicated, compulsive, concise, conduct, confined, confirmed, conflict, confusing, conjunction, conservation, consistent, constitutional, contain, contentious, contract, contribution, convene, convert, cooperation, coordination, corruption.