-our, suffix
(repr. AF. -our, OF. -or, -ur, -eör, -eür, mod.F. -eur), the earlier spelling of the suffix -or, regularly used in ME., and still commonly retained (in Great Britain, but not in America) in some of the words of ME. age, or of subsequent formation on the pattern of these; e.g. colour, honour, saviour, splendour, candour: see -or suffix.
b. In a few words, the suffix -our (= F. -eur), indicating state, is added to roots of Teutonic origin, as in dreadour, quenchour, raddour, q.v.
c. -our is in some words a corruption or alteration of some other ending, as in arbour, armour, behaviour, demeanour, endeavour, harbour, haviour, neighbour, parlour, q.v.