tropaeolin

== English == === Alternative forms === tropeolin tropæolin (obsolete) === Etymology === From Tropaeolum +‎ -in. === Noun === tropaeolin (countable and uncountable, plural tropaeolins) Any of several orange dyes of very complex composition: tropaeolin O (acid orange 6, chrysoine resorcinol), tropaeolin OO (acid orange 5), or tropaeolin OOO (acid orange 7).