1
: the protuberance of a mammary gland upon which in the female the lactiferous ducts open and from which milk is drawn
2
a
: an artificial teat through which a bottle-fed infant nurses
b
: a device with an orifice through which the discharge of a liquid can be regulated
3
a
: a protuberance resembling or suggesting the nipple of a breast
b
: a small projection through which oil or grease is injected into machinery
4
: a pipe coupling consisting of a short piece of threaded tubing
Cite this Entry
“Nipple.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nipple. Accessed 7 Jul. 2026.
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