*vermilion*

n. [ F. vermillon. See Vermeil. ] 1. (Chem.) A bright red pigment consisting of mercuric sulphide, obtained either from the mineral cinnabar or artificially. It has a fine red color, and is much used in coloring sealing wax, in printing, etc. [ 1913 Webster ]

☞ The kermes insect has long been used for dyeing red or scarlet. It was formerly known as the worm dye, vermiculus, or vermiculum, and the cloth was called vermiculatia. Hence came the French vermeil for any red dye, and hence the modern name vermilion, although the substance it denotes is very different from the kermes, being a compound of mercury and sulphur. R. Hunt. [ 1913 Webster ]

2. Hence, a red color like the pigment; a lively and brilliant red; as, cheeks of vermilion. [ 1913 Webster ]