英语词源字典 - 在线词源网站

unpleasant (adj.)[unpleasant 词源字典]: 1530s, from un- (1) "not" + pleasant (adj.). Related: Unpleasantly. [unpleasant etymology, unpleasant origin, 英语词源]
gunge: "An unpleasantly sticky or viscous substance", 1960s: perhaps suggested by goo and gunk.