Old English sealf "healing ointment," from West Germanic *salbo- "oily substance" (source also of Old Saxon salba, Middle Dutch salve, Dutch zalf, Old High German salba, German salbe "ointment"), from PIE *solpa-, from root *selp- "fat, butter" (source also of Greek elpos "fat, oil," Sanskrit sarpis "melted butter"). The figurative sense of "something to soothe wounded pride, etc." is from 1736.