Толковый словарь английского языка Oxford English Reference - donkey

n. (pl. -eys) 1 a domestic ass. 2 colloq. a stupid or foolish person. Phrases and idioms donkey engine a small auxiliary engine. donkey jacket a thick weatherproof jacket worn by workers and as a fashion garment. donkey's years colloq. a very long time. donkey-work the laborious part of a job; drudgery. Etymology: earlier with pronunc. as monkey: perh. f. DUN(1), or the Christian name Duncan