"light stick used by painters to support the painting hand," 1650s, from Dutch maalstok, literally "painting stick," from mallen "to paint," from Proto-Germanic *mal- (source also of Old Norse mæla, Old High German malon "trace, draw, paint," German malen "to paint"), from mal "spot, mark, stain," perhaps from the same root as Greek melas "black" (see melano-), but the original sense is not color but marking. With stock "stick" (see stock (n.1)).
"arsenic trisulphide," a bright yellow mineral substance used in dyeing as a pigment and also medicinally and for destroying lice, late 13c., orpyment, from Old French orpiment "arsenic trisulphide, yellow color," from Latin auripigmentum, from aurum "gold" (see aureate) + pigmentum "coloring matter, pigment, paint," from stem of pingere "to color, paint," from a nasalized form of PIE root *peig- "to cut, mark by incision."
1951, proprietary name (Dane & Co. of London) for a brand of fluorescent paint. As an adjective, with reference to colors and patterns, by 1959.
"first coat of paint or other material given to any surface," c. 1600, verbal noun from prime (v.). Meaning "act of priming a firearm" is by 1590s; that of "gunpowder in the pan of a firearm" is from 1620s.