What is the X in X-mas?
"rich brown pigment," 1821, from Italian seppia "cuttlefish" (borrowed with that meaning in English by 1560s), from Latin sepia "cuttlefish," from Greek sepia "cuttlefish," related to sepein "to make rotten" (cf. sepsis). The color was that of brown paint or ink prepared from the fluid secretions of the cuttlefish. Meaning "a sepia drawing" is recorded from 1863.
dyestuff, coloured brown with a trace of violet, that is obtained from a pigment protectively secreted by cuttlefish or squid. Sepia is obtained from the ink sacs of these invertebrates. The sacs are speedily extracted from the bodies and are dried to prevent putrefaction. The sacs are then dissolved in dilute alkali, and the resulting solution is filtered. The pigment thus obtained is precipitated with dilute hydrochloric acid and is then washed, filtered, and dried. The chemically inert pigment is fairly permanent and is used as a drawing ink and as an artist's watercolour, particularly in monochrome