nipple
/ˈnɪpl; `nɪpl/ n
1
(a) small projection on the breast through which a baby sucks its mother's milk （女子的）乳头, 奶头.
(b) similar projection on the chest of a human male （男子的）乳头. Cf 参看 teat. =>illus at human 见human插图.
2 = teat.
3 thing shaped like a nipple 似乳头之物
`grease nipples, ie for squirting grease into machinery 油脂喷嘴.