1 hour ago, IndyRob said:The OED may be definitive for Oxford, but not elsewhere.
The OED is resolutely international and takes in all varieties of English. It has more lexicographers working in the USA than anywhere else. It is certainly NOT confined to Oxford.
God knows what wikipedia is definitive of. Comparing it with the OED in terms of authority is hilarious. There is a good reason why citing wikipedia as a source is banned in many academic institutions.