tropaeolin

noun

tro·​pae·​o·​lin

variants or tropeolin

trōˈpēələ̇n

plural -s

often capitalized

: any of several orange or orange-yellow azo dyes some of which (as methyl orange) are used as acid-base indicators or as biological stains

Word History

Etymology

International Scientific Vocabulary tropaeol- (from New Latin Tropaeolum) + -in

First Known Use

1878, in the meaning defined above

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