"organ of hearing," Old English eare "ear," from Proto-Germanic *auzon (cf. Old Norse eyra, Danish øre, Old Frisian are, Old Saxon ore, Middle Dutch ore, Dutch oor, Old High German ora, German Ohr, Gothic auso), from PIE *ous- with a sense of "perception" (cf. Greek aus, Latin auris, Lithuanian ausis, Old Church Slavonic ucho, Old Irish au "ear," Avestan usi "the two ears").
The belief that itching or burning ears means someone is talking about you is mentioned in Pliny's "Natural History" (77 C.E.). Until at least the 1880s, even some medical men still believed piercing the ear lobes improved one's eyesight. Meaning "handle of a pitcher" is mid-15c. (but cf. Old English earde "having a handle"). To be wet behind the ears "naive" is implied from 1914. Phrase walls have ears attested from 1610s. Ear-bash (v.) is Australian slang (1944) for "to talk inordinately" (to someone).