from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. Any of a series of blue, bluish-red and black dyestuffs, formed by the interaction of para-amino azo compounds with primary monoamines in the presence of a small quantity of a mineral acid.
from the GNU version of the Collaborative International Dictionary of English
- n. Any one of a large series of aniline dyes, colored blue or violet, and represented by aniline violet.
- n. A dark green amorphous dyestuff, produced by the oxidation of aniline in the presence of copper or vanadium salts; -- called also aniline black.
from The Century Dictionary and Cyclopedia
- n. A name of various coaltar colors used in dyeing.
Perhaps from indigo. (Wiktionary)