Oxford spelling

Oxford spelling (also Oxford English Dictionary spelling, Oxford style, or Oxford English spelling) is the spelling standard used by the Oxford University Press (OUP) for British publications, including its Oxford English Dictionary (OED) and its influential British style guide Hart's Rules, and by other publishers who are "etymology conscious", according to Merriam-Webster.

Oxford spelling is best known for its preference for the suffix -ize in words like organize and recognize, versus the -ise endings that are more common in current British English usage. The spelling affects about 200 verbs and is favoured because -ize corresponds more closely to the Greek root, -izo (-ιζω), of most -ize verbs. In addition to the OUP's "Oxford"-branded dictionaries, other British dictionary publishers that list -ize suffixes first include Cassell, Collins and Longman. Oxford spelling is used by many British academic/science journals (for example, Nature) and many international organizations (for example, the United Nations). It is common for academic, formal, and technical writing for an international readership (see Usage). In digital documents, Oxford spelling may be indicated by the IETF language tag en-GB-oxendict (or, historically, by en-GB-oed).

Oxford spelling can be recognized by its use of the suffix ‑ize instead of -ise: organization, privatize and recognizable, instead of organisation, privatise and recognisable. The spelling affects about 200 verbs, and is favoured on etymological grounds, in that -ize corresponds more closely to the Greek root, -izo, of most -ize verbs. The suffix -ize has been in use in the UK since the 15th century, and is the spelling variation used in American English. The belief that -ize is an exclusively American variant is incorrect. The OED lists the -ise form of words separately, as "a frequent spelling of -IZE…":

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