British English words end in ‘our’
colour
flavour
humour
neighbour
British English verbs end with ‘ize’ or ‘ise’
apologize or apologise
organize or organise
recognize or recognise
analyse
British English nouns end with ‘ence’
defence
licence
offence
American English words end in 'or'
color
flavor
humor
neighbor
American verbs end with ‘ize’
apologize
organize
recognize
analyze
American English nouns end with ‘ense'
defense
license
offense