The word derives from the Greek symbolon meaning token or watchword. It is an amalgam of syn- "together" + bole "a throwing, a casting, the stroke of a missile, bolt, beam." The sense evolution in Greek is from "throwing things together" to "contrasting" to "comparing" to "token used in comparisons to decide if something is genuine." Hence, "outward sign" of something. The meaning "something which stands for something else" was first recorded in 1590, in Edmund Spenser's Faerie Queene.