Replaced Middle English ynde (late 13c., from Old French inde "indigo; blue, violet" (13c.), from Latin indicum). Earlier name in Mediterranean languages was annil, anil (see aniline). As "the color of indigo" from 1620s. As the name of the violet-blue color of the spectrum, 1704 (Newton).
chemical base used in making colorful dyes, 1843, coined 1841 by German chemist Carl Julius Fritzsche and adopted by Hofmann, ultimately from Portuguese anil "the indigo shrub," from Arabic an-nil "the indigo," assimilated from al-nil (with Arabic definite article al-), from Persian nila, ultimately from Sanskrit nili "indigo," from nilah "dark blue."
With suffix -ine indicating "derived substance" (see -ine (1); also see -ine (2) for the later, more precise, use of the suffix in chemistry). Discovered in 1826 in indigo and at first called crystallin; it became commercially important in 1856 when mauve dye was made from it. As an adjective from 1860.
Old English wad "woad," also the blue dye made from its leaves, from Proto-Germanic *waidīn (source also of Danish vaid, Old Frisian wed, Middle Dutch wede, Dutch wede, Old High German weit, German Waid "woad"), which is perhaps cognate with Latin vitrium "glass" (see vitreous), but Boutkan considers it a substratum word. Formerly much cultivated; since superseded by indigo. French guède, Italian guado are Germanic loan-words.