indigo blue

noun

1. indigo.

2. Also called indigo, indigotin. a dark-blue, water-insoluble, crystalline powder, C 16 H 10 N 2 O 2 , having a bronzelike luster, the essential coloring principle of which is contained along with other substances in the dye indigo and which can be produced synthetically.

indigo blue

noun

1. the full name for indigo indigo

Other Word Forms

• indigo-blue adjective

Word History and Origins

Origin of indigo blue¹

First recorded in 1705–15