aff. use a suffix occurring in loanwords from Latin, directly or through Anglo-French, usu. denoting a condition or property of things or persons, sometimes corresponding to qualitative adjectives ending in -id IV (honor; horror; liquor; pallor); a few other words that orig. ended in different suffixes have been assimilated to this group (behavior; demeanor; glamour)•Etymology: < L; in some cases continuing ME -our < AF, OF < L -ōr-, s. of -or, earlier -os usage: The -or spelling of the suffix -or is characteristic of American English, with occasional exceptions. In British English -our is still the most common spelling, -or often being retained when certain suffixes are added, as in coloration, honorary, and laborious. The English of Australia, New Zealand, and South Africa tends to mirror British practice, whereas Canadian English is about equally divided between U.S. and British forms.―The suffix -or is now spelled -or in all forms of English, except for the word savior, once often spelled saviour in the U.S. as in Britain, esp. with reference to Jesus. But the official spelling of Catholics, Episcopalians, Presbyterians, and Methodists is now savior; saviour is now only British. II-oraff. a suffix forming animate or inanimate agent nouns, occurring orig. in loanwords from Anglo-French (debtor; tailor; traitor); it now functions in English as an orthographic variant of -er I, usu. joined to bases of Latin origin, in imitation of borrowed Latin words containing the suffix -tor (and alternant -sor). Resultant formations often denote machines or less tangible entities that behave in an agentlike way:projector; repressor; sensor; tractor[/ex]•Etymology: ME < AF, OF -o(u) r < L -ōr; cf. -eur usage: See -or .
From formal English to slang. 2014.