4. The edema / oedema group

4. The edema / oedema group

In words of Greek origin, GB English has oe- where US English has e- or less commonly oe-. Similarly, words with an ae combination in GB English (orthopaedics, anaesthesia) are spelt without the a in US English. To see the full text, click here.

AE	BE
anemia	anaemia
anemic	anaemic
anesthetic	anaesthetic
anesthetist	anaesthetist
cesarean	caesarean
diarrhea	diarrhoea
edema	oedema
enology, oenology	oenology
esophagus	oesophagus
estrogen	oestrogen
estrus	oestrus
fecal	faecal
feces	faeces
fetal	foetal
fetus	foetus
gonorrhea	gonorrhoea
gynecology	gynaecology
hemoglobin	haemoglobin
hemophilia	haemophilia
hemorrhage	haemorrhage
hemorrhoid	haemorrhoid
leukemia	leukaemia
maneuver	manoeuvre
orthopedics, orthopaedics	orthopaedics
Paleolithic	Palaeolithic
Paleozoic	Palaeozoic

3. The realize / realise group

3. The realize / realise group

In this group, differences between GB and US spelling are far from systematic. Some verbs, regardless of the country, can only have -ize (capsize, seize) while in others only -ise is possible (advertise, advise, surprise). Dictionaries in both countries prefer the suffix -ize in words such as apologize, legalize and realize. Many Britons, however, (not to mention the spelling checkers of popular word-processing programs) do not agree with the dictionary-makers and in GB these words are still usually written with -ise. To see the full text, click here.

AE	BE
aggrandize	aggrandize, aggrandise
Americanize	Americanise, Americanize
apologize	apologise, apologize
burglarize	burglarise, burglarize
capitalize	capitalise, capitalize
categorize	categorise, categorize
characterize	characterise, characterize
colonize	colonise, colonize
criticize	criticise, criticize
dramatize	dramatise, dramatize
emphasize	emphasize, emphasise
equalize	equalise, equalize
extemporize	extemporise, extemporize
finalize	finalize, finalise
liberalize	liberalize, liberalise
mobilize	mobilise, mobilize
naturalize	naturalise, naturalize
normalize	normalize, normalise
organize	organise, organize
popularize	popularise, popularize
realize	realise, realize
recognize	recognise, recognize
satirize	satirise, satirize
stabilize	stabilize, stabilise
standardize	standardise, standardize
symbolize	symbolise, symbolize
vaporize	vaporise, vaporize

2. The center / centre group

2. The center / centre group

Most GB words ending in -tre, usually deriving from French, end in -ter in the US. This difference is also apparent in derivatives. To see the full text, click here.

AE	BE
accoutre, accouter	accoutre
accouterment, accoutrement	accoutrement
amphitheater	amphitheatre
caliber, calibre	calibre
center	centre
centerfold	centrefold
fiber, fibre	fibre
fiberboard, fibreboard	fibreboard
fiberglass, fibreglass	fibreglass
goiter	goitre
liter	litre
luster	lustre
maneuver	manoeuvre
meager, meagre	meagre
meter	metre
miter, mitre	mitre
niter	nitre
ocher, ochre	ochre
philter, philtre	philtre
reconnoiter, reconnoitre	reconnoitre
saber, sabre	sabre
saltpeter	saltpetre
scepter	sceptre
somber, sombre	somber
specter, spectre	spectre
theater, theatre	theatre

1. The color / colour group

1. The color / colour group

Most GB words ending in -our end in -or in the US. This difference is also apparent in derivatives. To see the full text, click here.

AE	BE
arbor	arbour
ardor	ardour
armor	armour
armorer	armourer
armory	armoury
behavior	behaviour
behavioral	behavioural
candor	candour
clamor	clamour
color	colour
demeanor	demeanour
enamor	enamour
endeavor	endeavour
favor	favour
favorite	favourite
favoritism	favouritism
fervor	fervour
flavor	flavour
glamor,glamour	glamour
harbor	harbour
honor	honour
humor	humour
labor	labour
misdemeanor	misdemeanour
neighbor	neighbour
neighborhood	neighbourhood
odor	odour
parlor	parlour
rancor	rancour
rigor	rigour
rumor	rumour
savior	saviour
savor, savour	savour
splendor	splendour
succor	succour
tumor	tumour
valor	valour
vapor	vapour
vigor	vigour