eu·on·y·min \yüˈänəmə̇n\noun (-s) Etymology: International Scientific Vocabulary euonym- (from New Latin Euonymus, genus name of Euonymus atropurpureus) + -in — more at euonymus : a mixture of impure active principles derived from a wahoo (Euonymus atropurpureus); also: the dry powdered extract of this plant