: any of several hardy gregarious (see gregarioussense 1a) African or Asian perissodactyl mammals (genus Equus) smaller than the horse and having long ears
especially: an African mammal (E. asinus) that is the ancestor of the donkey
2
informal + impolite: a stupid, stubborn, or detestable person
a pompous ass
made an ass of himself
He was an ass to her, dissing her script (which he apparently lost), telling her women couldn't be artists and that she looked so much prettier with makeup on. Lauren Piester