Oxford spelling (alsoOxford English Dictionary spelling,Oxford style, orOxford English spelling) is a spelling standard, named after its use by theOxford University Press, that prescribes the use ofBritish spelling in combination with the suffix-ize in words likerealize andorganization instead of-ise endings.

Oxford spelling is used by many UK-based academic journals (for example,Nature) and many international organizations (for example, theUnited Nations and its agencies).^[1][2][3] It is common for academic, formal, and technical writing for an international readership. In digital documents, Oxford spelling may be indicated by theIETF language tagen-GB-oxendict (or historically byen-GB-oed).^[4]

Oxford spelling uses the suffix‑ize alongside‑lyse:organization,privatize andrecognizable, rather thanorganisation,privatise andrecognisable – alongsideanalyse,paralyse etc. TheOxford University Press states that the belief that‑ize is an exclusively North American variant is incorrect.^[5] The Oxford spelling affects about 200 verbs,^[6] and is favoured on etymological grounds, in that‑ize corresponds more closely to theGreekroot of most‑ize verbs,-ίζω (‑ízō).^[7]

The suffix‑ize has been in use in the UK since the 15th century,^[5] and is the spelling variation used inNorth American English. TheOxford English Dictionary lists the‑ise form of words separately, as "a frequent spelling of ‑IZE ...":

This practice probably began first in French; in modern French the suffix has become‑iser, alike in words from Greek, asbaptiser, évangéliser, organiser, and those formedafter them from Latin, asciviliser, cicatriser, humaniser.

Hence, some have used the spelling ‑ise in English, as in French, for all these words, and some prefer ‑ise in words formed in French or English from Latin elements, retaining ‑ize for those formed from Greek elements.

However, the suffix itself, whatever the element to which it is added, is in its origin the Greek‑ιζειν, Latin‑izāre; and, as the pronunciation is also with z, there is no reason why in English the special French spelling should be followed, in opposition to that which is at once etymological and phonetic. In this Dictionary the termination is uniformly written ‑ize. (In the Greek‑ιζ‑, the i was short, so originally in Latin, but the double consonant z (= dz, ts) made the syllable long; when the z became a simple consonant, /‑idz/ became īz, whence English /‑aɪz/.)

The Oxford use of‑ize does not extend to the spelling of words not traced to the Greek‑izo,‑izein suffixes. One group of such words is those ending in‑lyse, such asanalyse,paralyse andcatalyse, which come from the Greek verbλύω,lyo, the perfective (aorist) stem of which is‑lys-: for these,‑lyse is the more etymological spelling. Others includeadvertise,arise,compromise,chastise,disguise,improvise,prise (in the sense of open), andtelevise.^{[additional citation(s) needed][8]}

In addition to the OUP's "Oxford"-branded dictionaries, other British dictionary publishers that list‑ize suffixes first includeCassell,Collins, andLongman.^[9]

Oxford spelling is used by theOxford University Press (OUP) for British publications,^[10] including itsOxford English Dictionary and its influential British style guideHart's Rules, and by other publishers who are "etymology conscious", according toMerriam-Webster.^[11]

Oxford spelling (especially the first form listed in theConcise Oxford English Dictionary, Twelfth Edition) is the official orde facto spelling standard used in style guides of the international organizations that belong to theUnited Nations System.^[2] This includes theWorld Health Organization, theInternational Telecommunication Union, theInternational Labour Organization, theWorld Food Programme, theInternational Court of Justice, andUNESCO, and all UN treaties and declarations, such as theUniversal Declaration of Human Rights.^[12]

Other international organizations that adhere to this standard include theInternational Organization for Standardization (ISO), theInternational Electrotechnical Commission (IEC), theWorld Trade Organization (WTO), theNorth Atlantic Treaty Organization (NATO), theInternational Atomic Energy Agency (IAEA),Interpol, theInternational Committee of the Red Cross (ICRC), theWorld Wide Fund for Nature (WWF),Amnesty International (AI), theWorld Economic Forum (WEF) and theGlobal Biodiversity Information Facility (GBIF).^[12][13]

Oxford spelling is used in a number of academic publications, including the London-based scientific journalNature and all other UK-based "Nature"-branded journals, thePhilosophical Transactions of the Royal Society, and theJournal of Physiology. It is used byThe Times Literary Supplement,Encyclopædia Britannica andCambridge University Press.^[12] Newspapers and magazines in the UK normally use-ise. The style guide ofThe Times recommended-ize until 1992, when it switched to-ise.^[8] The newspaper's chief revise editor, Richard Dixon, wrote of the change:^[8]

In the great -ize versus -ise debate,The Times has opted latterly for simplicity over a sort of erudition ... But in theStyle Guide of 1992, the following entry appeared: "-ise, -isation: avoid the z construction in almost all cases. This is volcanic ground, with common usage straining the crust of classical etymology. This guidance is a revision of the Greek zeta root ending in the direction of a Latin ending and common usage: apologise, organise, emphasise, televise, circumcise. The only truly awkward result is capsize, which should be left in its Grecian peace."

In both theKing James Bible and the works ofShakespeare,-ize endings are used throughout.^{[additional citation(s) needed]} Well-known literary works that use Oxford spelling includeThe Lord of the Rings byJ. R. R. Tolkien (anOxford University professor),And Then There Were None byAgatha Christie (married to anAll Soulsarchaeologist), andThe Lion, the Witch and the Wardrobe byC. S. Lewis (afellow ofMagdalen College, Oxford).

Oxford spelling is not necessarily followed by the staff of theUniversity of Oxford. The university's style guide, last updated in 2016, recommended the use of-ise for internal use.^[14]

The following table summarizes a few general spelling differences among five major English spelling conventions, plus the French spelling convention for comparison. Note:en-GB simply stands for British English; it is not specified whether-ize or-ise should be used. Thelanguage tagen-GB-oxendict, however, demands the use of-ize and-ization.

• Canadian English spelling
• Macquarie Dictionary (Australian usage)
• Oxford comma
• Spelling differences: -ise, -ize

• The Oxford English Dictionary (1st ed.)
• The Oxford English Dictionary 2nd ed. (20 vols.)
• The Oxford English Dictionary, Oxford: Oxford University Press (latest edition: on WWW)

• IANA Language Tag Registration Form foren-GB-oed
• AskOxford: Are spellings likeprivatize andorganize Americanisms?
• British Medical Journal:-ize right
• World Wide Words: The endings "-ise" and "-ize"
• Detailed blog post about -ise and -ize verbs in British English.
• Tieken-Boon Van Ostade, Ingrid.An Introduction to Late Modern English. Edinburgh University Press, 2009, p. 38.

• 15th-century introductions
• American and British English differences
• Culture in Oxford
• English orthography
• Oxford English Dictionary

• Articles containing explicitly cited Australian English-language text
• Articles containing Middle English (1100-1500)-language text
• Articles containing French-language text
• Articles containing Ancient Greek (to 1453)-language text
• Articles with short description
• Short description is different from Wikidata
• Use Oxford spelling from May 2024
• Use dmy dates from May 2024
• Articles containing Latin-language text
• All articles needing additional references
• Articles needing additional references from April 2024
• Articles containing explicitly cited English-language text
• Articles containing explicitly cited British English-language text
• Articles containing explicitly cited Canadian English-language text
• Articles containing explicitly cited American English-language text