ˈind(y)əˌlēn, -_lə̇n noun
( -s )
Usage: usually capitalized
Etymology: International Scientific Vocabulary ind- + -ule + -ine
: any of a class of blue or violet dyes related to the safranines: as
a. : a reddish to greenish blue dye derived from phenosafranine and made by heating amino-azobenzene and aniline in the presence of hydrochloric acid — called also Induline Spirit Soluble ; see dye table I (under Solvent Blue 7 )
b. : a water-soluble acid dye made by sulfonating the free base obtained by treating Induline Spirit Soluble with alkali — see dye table I (under Acid Blue 20 )