1. The color / colour group

1. The color / colour group

Most GB words ending in -our end in -or in the US. This difference is also apparent in derivatives. To see the full text, click here. 

AE	BE
arbor	arbour
ardor	ardour
armor	armour
armorer	armourer
armory	armoury
behavior	behaviour
behavioral	behavioural
candor	candour
clamor	clamour
color	colour
demeanor	demeanour
enamor	enamour
endeavor	endeavour
favor	favour
favorite	favourite
favoritism	favouritism
fervor	fervour
flavor	flavour
glamor,glamour	glamour
harbor	harbour
honor	honour
humor	humour
labor	labour
misdemeanor	misdemeanour
neighbor	neighbour
neighborhood	neighbourhood
odor	odour
parlor	parlour
rancor	rancour
rigor	rigour
rumor	rumour
savior	saviour
savor, savour	savour
splendor	splendour
succor	succour
tumor	tumour
valor	valour
vapor	vapour
vigor	vigour