If you know the meaning of the main prefixes (letters added at the beginning of a word) and suffixes (letters added to the end of a word), you have the key to a large number of new words made from words which you already know or which you may easily understand.
Here is a list of prefixes and suffixes (affixes) which may often be found in scientific English.
Abbreviations: adj = adjective; adv = adverb; n = noun; v = verb
PREFIXES
Prefixes are added to words to change their meaning.
| PREFIX | MEANING | USED WITH | EXAMPLES |
|---|---|---|---|
| a- (an-) | not, without, lacking in | adj, adv, n | aseptic, anaerobic; aseptically; asymmetry |
| dis- | not, opposite of | adj, adv, n, v | discolouring; discontinuously; disapproval; to disable |
| in- (il-, im-, ir-) | not, opposite of | adj, adv, n | inexhaustible, illegal, immeasurable, irregular; infinitely, illegally, impossibly, irregularly; infinity, illegality |
| un- | not, opposite of | adj, adv, n, v | unable; unconsciously; untruth; to unlock |
| non- | not, absence of | adj, adv, n | non-flammable, non-stop; non-proliferation |
| de- | opposite of, removal of | adj, adv, n, v | deficient; defectively; deforestation; to defrost |
| ab- | wrong | adj, n, v | abnormal; abuse; to abuse |
| mis- | bad(ly), wrong(ly) | n, v | misunderstanding; to misbehave |
| mal- | bad(ly), wrong(ly) | adj, n, v | malodorous; malnutrition; to malfunction |
| over- | too much | adj, adv, n, v | overfertilized; overpoweringly; overdose; to overestimate |
| under- | not enough | adj, n, v | underdeveloped; undernutrition; to underestimate |
| out- | surpassing | adj, adv, n, v | outsized; outstandingly; outbalance; to outnumber |
| fore- | in advance, in front of | n, v | foreground; to forecast |
| re- | again | adj, adv, n, v | recyclable; refreshingly; recycling; to readjust |