Open English Wordnet
Adjectives
(a)decorouscharacterized by propriety and dignity and good taste in manners and conduct“the tete-a-tete was decorous in the extreme” (s)becoming, comely, comme il faut, decorous, seemlyaccording with custom or propriety“her becoming modesty”,
“comely behavior”,
“it is not comme il faut for a gentleman to be constantly asking for money”,
“seemly behavior”