Prefixes from Greek

A prefix is a small sub-unit of language: it is a letter or group of letters placed at the beginning of a word to form a new word with a different meaning from the original word.

Many prefixes in English derive from the Classical Languages, i.e., from Greek and Latin. Many, though not all, of them were prepositions in Greek or Latin, and many, though not all, also functioned as prefixes in those languages.

Here is a list of the more common prefixes which have a Greek origin. (For a list of the more common prefixes which have a Latin origin see Prefixes from Latin.) The first column lists the basic form of the prefix, while the last column lists some of the ways in which the prefix can be modified. For example, the English word 'sympathy' is a combination of the prefix 'syn-' (with, together) and the Greek word pathos {feeling}, but before words beginning with 'p' 'syn' is modified to 'sym-' because the combination 'mp' is much easier to pronounce than the combination 'np'.

Prefix	Meaning	Examples	Other forms of the prefix
a-	not, without	apathetic, atheism	Often an- before a vowel, as in 'anodyne' and 'anonymous'
amphi-	around, both	amphitheatre, amphibian
ana-	up, again, back	anatomy, analysis, analogy
anti-	against, opposite	antifreeze, antipathy, antidote
apo-	away from, off	apology, apostate, apogee	aph- before a vowel where the original Greek word began with an 'h', as in 'aphorism' (pronounced '-f-') and 'aphelion' ('p'-'h' separately)
arch-	chief, principal	archangel, archbishop	sometimes archi- as in 'architect'
auto-	self, same	autobiography, autodidact, autocrat, automobile
cata-	down, downwards, badly	cataract, catastrophe	cath- before a vowel where the original Greek word began with 'h', as in 'cathode'
di-	two, double	dilemma, dioxide
dia-	through, across, apart	dialogue, dialysis, diameter	di- before a vowel, as in 'diaeresis'
dys-	bad, abnormal	dysfunctional, dyspepsia, dystrophy
ec-	from, out of	eccentric, eclectic	ex- before a vowel, as in 'exodus'
epi-	upon, above	epicentre, epitaph, epithet	eph- before a vowel where the original Greek word began with an 'h', as in 'ephemeral'
eu-	well, good	eulogy, euphoria, euthanasia, euphony
hyper-	over, excessive	hyperactive, hypersensitive, hyperbole
hypo-	under, below normal	hypotenuse, hypothermia	hyph- before a vowel where the original Greek word began with an 'h', as in 'hyphen'
meta-	behind, after, change	metamorphosis, metabolism, metaphor	meth- before a vowel where the original Greek word began with 'h', as in 'method'
mono-	one, single	monologue, monograph, monolith	mon- before a vowel, as in 'monocle' from 'ocul[ar]'
neo-	new, recent	neonate, neologism, neoclassical
para-	beside, beyond	paradox, paramilitary	par- before a vowel, as in 'parallel'
palin-	back, backwards, again	palinode, palindrome	palim- before 'p', as in 'palimpsest'
peri-	round, about	periscope, perinatal, peripheral
poly-	many, much	polygamy, polymath, polychrome
pro-	before, forward	prologue, prophet, programme
syn-	with, together	synchronise, synthetic	sym- before 'b' and 'p', as in 'symbol' and 'sympathy'; syl- before 'l', as in 'syllable'