Of Latin origin; the "purple" mussel, i.e. (by implication) the red-blue color itself, and finally a garment dyed with it -- purple.
1. the purple-fish, a species of shell-fish or mussel: (Aeschylus, Sophocles), Isocrates, Aristotle, others; add 1 Macc. 4:23, on which see Grimm; (cf. B. D., under the word 2. a fabric colored with the purple dye, a garment made from purple cloth (so from Aeschylus down): Mark 15:17, 20; Luke 16:19; Revelation 17:4 Rec.;