Decorous(a.) Suitable to a character, or to the time, place, and occasion; marked with decorum; becoming; proper; seemly; befitting; as, a decorous speech; decorous behavior; a decorous dress for a judge.
Thesaurus Entries
Christian, accepted, according to Hoyle, acknowledged, admitted, appropriate, approved, au fait, becoming, befitting, being done, ceremonial, ceremonious, civil, civilized, comely, comme il faut, condign, conformable, conforming, conventional, correct, customary, de rigueur, decent, delicate, demure, dignified, done, due, earnest, elegant, felicitous, fit, fitting, formal, frowning, genteel, gentlemanly, good, grave, grim, grim-faced, grim-visaged, happy, hieratic, kosher, ladylike, liturgic, long-faced, mannerly, meet, modest, nice, normal, normative, orthodox, polished, polite, pompous, prim, proper, punctilious, received, recognized, refined, respectable, right, right and proper, righteous, rightful, rigid, ritual, ritualistic, sacerdotal, seasonable, sedate, seemly, serious, sober, sober-minded, sobersided, solemn, somber, staid, stately, stiff, stone-faced, straight-faced, stuffy, suitable, thoughtful, traditional, unsmiling, urbane, weighty, well-behaved, well-mannered