Wikipedia:List of spelling variants

This is a list of British English words that have different American English spellings, for example, colour (British English) and color (American English).

Word pairs are listed with the British English version first, in italics, followed by the American English version:

• spelt, spelled

Derived words often, but not always, follow their root. Thus "neighbour/neighbor" give "neighbourly/neighborly", "neighbouring/neighboring" etc. (but "licensing" is used everywhere, in spite of "licence/license"). Plurals and verb forms almost always follow even though not listed here: "analyses/analyzes", "analysed/analyzed" etc. (but note "analysis" is universal).

Some usages identified as American English are common in British English; e.g., disk for disc. A few listed words are more different words than different spellings: "aeroplane/airplane", "mum/mom".

See also: American and British English differences, Wikipedia:List of common misspellings and Wikipedia:Manual of Style#National varieties of English

A

• acknowledgement, acknowledgment
• adze, adz
• aeroplane /ˈɛərəpleɪn/, airplane /ˈɛərpleɪn/
• aluminium /ˌæljəˈmɪniːəm/, aluminum /əˈluːmɪnəm/ – but note that Wikipedia usage for chemistry-related articles is always aluminium as specified by IUPAC
• anaemia, anemia
• anaesthesia, anesthesia
• analyse, analyze
• analogue, analog (Note: analogue is the preferred U.S. spelling for the noun; however, analog is also acceptable.)
• annexe, annex
• apologise, apologize
• armour, armor
• arse /ɑːrs/, ass /æs/ – except when referring to donkeys, universally "ass"
• artefact, artifact
• authorise, authorize
• axe, ax

B

• behaviour, behavior

C

• caesium, cesium – but note that Wikipedia usage for chemistry-related articles is always caesium as specified by IUPAC
• cancelled, canceled
• cancelling, canceling
• carburettor, carburetor
• catsup, ketchup
• centre, center
• cheque, check – for the financial document only
• chequer, checker
• chilli, chili (both spellings abound).
• cypher, cipher
• civilise, civilize – and derived words
• colonise, colonize
• colonisation, colonization
• colour, color
• connexion, connection - but connection is now universally more common except in a few British situations, e.g. the Methodist Church or "affine connexion" in mathematics
• cosy, cozy

D

• defence, defense
• despatch, dispatch
• diarrhoea, diarrhea
• dialogue, dialog
• disc, disk
• distil, distill
• doughnut, donut (see Doughnut § Etymology for the source of the short spelling)
• draught, draft
• dreamt /drɛmt/, dreamed /driːmd/

E

• emphasise, emphasize – and derived words
• encyclopaedia, encyclopedia
• enrolment, enrollment
• equalling, equaling
• endeavour, endeavor
• enquire, inquire

F

• favourite, favorite
• favour, favor
• faeces, feces
• fibre, fiber
• flaky, flakey
• foetid, fetid
• foetal, fetal
• foetus, fetus
• flautist, flutist
• flavour, flavor
• fulfil, fulfill
• furore, furor
• fuelling, fueling

G

• gaol, jail – but "jail" is common in British English now
• gasses, gases
• generalise, generalize
• glycerine, glycerin
• glueing, gluing
• grey, gray
• gynaecology, gynecology

H

• haemophilia, hemophilia
• haematology, hematology
• haem, heme
• harbour, harbor
• harmonise, harmonize
• harmonisation, harmonization
• homologue, homolog
• honour, honor
• humour, humor

I

• industrialise, industrialize
• instalment, installment
• italicise, italicize – and derived words.

J

• jewellery, jewelry
• judgement, judgment

K

• kerb, curb – both dialects use "curb" for the verb
• kilometre, kilometer

L

• labour, labor
• leapt /lɛpt/, leaped /liːpt/
• learnt /lɜːrnt/, learned /ˈlɜːrnɪd/ – past tense of to learn; an educated person is always learned
• leukæmia, leukemia
• licence (noun), license – but always licensing - see practice
• liquorice, licorice
• lit, lighted
• litre, liter
• lodgment, lodgement

M

• manoeuvre, maneuver
• marvellous, marvelous
• maths, math - as abbreviations for mathematics
• meagre, meager
• metre, meter – for the unit of length. In British English a meter is a measuring device
• modelling, modeling
• milliard, billion – 'billion' is now much more common in British English than 'milliard' (see Long and short scales)
• mould, mold
• mollusc, mollusk
• moult, molt
• mum, mom
• monologue, monolog
• moustache, mustache
• moisturiser, moisturizer

N

• neighbour, neighbor – and derived words

O

• oenology, enology
• oesophagus, esophagus
• oestrogen, estrogen
• odour, odor
• offence, offense
• omelette, omelet
• organisation, organization
• orthologue, ortholog
• orthopaedic, orthopedic

P

• paediatric, pediatric
• paedophile, pedophile
• paralyse, paralyze
• parlour, parlor
• pedagogue, pedagog
• plough, plow
• practise, practice – as a verb
• pretence, pretense
• prise, prize – the verb, meaning to lever
• programme, program – when not speaking of a computer program
• pyjamas, pajamas

Q

• quarrelled, quarreled
• quarrelling, quarreling

R

• realise, realize
• realisation, realization
• recognise, recognize – including ~ed/~ing/... variants
• rigour, rigor
• routeing, routing – defeating completely is always routing
• rumour, rumor

S

• sabre, saber
• saviour, savior
• savoury, savory
• sceptic, skeptic
• signalling, signaling
• skilful, skillful
• speciality, specialty
• spelt, spelled
• spoilt, spoiled – but note that in American and Canadian English, spoiled is both a past-tense verb (e.g. the milk spoiled) and a past-participial adjective (the spoiled milk). In British English, spoiled is usually the past-tense verb (the milk spoiled), and spoilt is usually the past-participial adjective (the spoilt milk)
• storey, story – a level of a building
• sulphur, sulfur – but note that Wikipedia usage for chemistry-related articles is always sulfur as specified by IUPAC root

T

• theatre, theater – theatre is sometimes used in the US
• tyre, tire – the component of a wheel
• tranquillity, tranquility
• travelled, traveled
• traveller, traveler
• travelling, traveling
• tumour, tumor
• too, to, two

U

• urbanisation, urbanization – and derived words.

V

• valour, valor

• vender, vendor
• vice or vyce, vise – when referring to the tool
• victual, vittle
• vigour, vigor

W

• wilful, willful
• wintery, wintry
• whisky, whiskey – the former is correct for Scottish spirits, the latter for those distilled elsewhere
• woollen, woolen

Y

• yoghurt, yogurt

Z

• zed, zee