a suffix occurring in loanwords from Latin, directly or through Anglo-French, usually denoting a condition or property of things or persons, sometimes corresponding to qualitative adjectives ending in (ardor; honor; horror; liquor; pallor; squalor; torpor; tremor); a few other words that originally ended in different suffixes have been assimilated to this group (behavior; demeanor; glamour).
a suffix forming animate or inanimate agent nouns, occurring originally in loanwords from Anglo-French (debtor; lessor; tailor; traitor); it now functions in English as an orthographic variant of, usually joined to bases of Latin origin, in imitation of borrowed Latin words containing the suffix(and its alternant -sor). The association with Latinate vocabulary may impart a learned look to the resultant formations, which often denote machines or other less tangible entities which behave in an agentlike way: descriptor; plexor; projector; repressor; sensor; tractor.