- a highly prized crimson or purple dye of classical antiquity, originally obtained at great expense from a certain shellfish: later shown to be an indigo derivative and synthetically produced, and now replaced by other synthetic dyes.
- a vivid, purplish red.
- a deep purple dye obtained from molluscs of the genus Murex and highly prized in antiquity
- a vivid purplish-red colour
- (as adjective)
