Prefix

Meaning

Examples

a-

also an-

not, without

atheist, anaemic

a-

to, towards

aside, aback

in the process of, in a particular state

a-hunting, aglow

a-

of

anew

completely

abashed

ab-

also abs-

away, from

abdicate, abstract

ad-

also a-, ac-, af-, ag- al-, an-, ap-, at- as-, at-

movement to, change into, addition or increase

advance, adulterate, adjunct, ascend, affiliate, affirm, aggravate, alleviate, annotate, apprehend, arrive, assemble, attend

ante-

before, preceding

antecedent, ante-room

anti-

also ant-

opposing, against, the opposite

anti-aircraft, antibiotic, anticlimax, Antarctic

be-

all over, all around

bespatter, beset

completely

bewitch, bemuse

having, covered with

bejewelled

affect with (added to nouns)

befog

cause to be (added to adjectives)

becalm

com-

also co-, col-, con-, cor-

with, jointly, completely

combat, codriver, collude, confide, corrode

contra-

against, opposite

contraceptive

counter-

opposition, opposite direction

counter-attack, counteract

de-

down, away

descend, despair, depend, deduct

completely

denude, denigrate

removal, reversal

de-ice, decamp

dia-

also di-

through, across

diagonal

dis-

also di-

negation, removal, expulsion

disadvantage, dismount, disbud, disbar

en-

also em-

put into or on

engulf, enmesh

bring into the condition of

enlighten, embitter

intensification

entangle, enrage

ex-

also e-, ef-

out

exit, exclude, expand

upward

exalt, extol

completely

excruciate, exasperate

previous

ex-wife

extra-

outside, beyond

extracurricular

hemi-

half

hemisphere

hyper-

beyond, more than, more than normal

hypersonic, hyperactive

hypo-

under

hypodermic, hypothermia

in-

also il-, im-

not, without

infertile, inappropriate, impossible

also il-, im-, ir-

in, into, towards, inside

influence, influx, imbibe

infra-

below

infrared, infrastructure

inter-

between, among

interact, interchange

intra-

inside, within

intramural, intravenous

non-

absence, negation

non-smoker, non-alcoholic

ob-

also oc-, of-, op-

blocking, against, concealing

obstruct, occult, offend, oppose

out-

surpassing, exceeding

outperform

external, away from

outbuilding, outboard

over-

excessively, completely

overconfident, overburdened, overjoyed

upper, outer, over, above

overcoat, overcast

peri-

round, about

perimeter

post-

after in time or order

postpone

pre-

before in time, place, order or importance

pre-adolescent, prelude, precondition

pro-

favouring, in support of

pro-African

acting for

proconsul

motion forwards or away

propulsion

before in time, place or order

prologue

re-

again

repaint, reappraise, reawake

semi-

half, partly

semicircle, semi-conscious

sub-

also suc-, suf-, sug-, sup-, sur-, sus-

at a lower position

submarine, subsoil

lower in rank

sub-lieutenant

nearly, approximately

sub-tropical

syn-

also sym-

in union, acting together

synchronize, symmetry

trans-

across, beyond

transnational, transatlantic

into a different state

translate

ultra-

beyond

ultraviolet, ultrasonic

extreme

ultramicroscopic

un-

not

unacceptable, unreal, unhappy, unmanned

reversal or cancellation of action or state

unplug, unmask

under-

beneath, below

underarm, undercarriage

lower in rank

undersecretary

not enough

underdeveloped