1. (noun)wing nut, wing-nut any tree of the genus Pterocarya; fruit is a small winged nutlet; Caucasus to southeastern Asia Synonyms: wingscrew, wing nut, butterfly nut, thumbnut, wing-nut
2. (noun)wing nut, wing-nut, wing screw, butterfly nut, thumbnut a threaded nut with winglike projections for thumb and forefinger leverage in turning Synonyms: wingscrew, wing nut, butterfly nut, thumbnut, wing-nut