Old English ule "owl," from Proto-Germanic *uwwalon- (cognates: Middle Dutch, Dutch uil, Old High German uwila, German Eule, Old Norse ugla), a diminutive of PIE root *u(wa)l-, which is imitative of a wail or an owl's hoot (compare Latin ulula "owl;" also see ululation). The bird was employed proverbially and figuratively in reference to nocturnal habits, ugliness, and appearance of gravity and wisdom (often ironic).