Origin and history of nipple

"beak or bill of a bird," Old English nebb "beak, nose; human face, countenance; beak-shaped thing," from Proto-Germanic nabja "beak, nose" (source also of Old Norse nef "beak, nose," Middle Dutch nebbe "beak," Old High German snabul, German Schnabel "beak," Old Frisian snavel "mouth"), which is of uncertain origin.

"nipple of a woman's breast," late 12c., pappe, first attested in Northern and Midlands writing, probably from a Scandinavian source (not recorded in Old Norse, but compare dialectal Swedish pappe), from PIE imitative root *pap- "to swell" (source also of Latin papilla "nipple," which might rather be the source of the English word, papula "a swelling, pimple;" Lithuanian papas "nipple"). Like pap (n.1) supposed to be ultimately of infantile origin.

c. 1200, perhaps late Old English, tete, "a nipple; a breast, human female mammary gland," from Old French tete "teat" (12c., Modern French tette), from Proto-Germanic *titta (source of Old English titt, see tit (n.1)). Spanish teta, Italian tetta are from the same source. Applied to the nipples of human males by mid-14c. Middle English had teatly "shaped like a nipple" (early 15c.).