adj. 1 impolite or offensive. 2 roughly made or done; crude (rude plough). 3 primitive or uneducated (rude simplicity). 4 abrupt, sudden, startling (rude awakening). 5 colloq. indecent, lewd (rude joke). 6 vigorous or hearty (rude health). o. rudely adv. rudeness n. [Latin rudis]