NIPPLE

noun Etymology: earlier neble, nible, probably diminutive of neb, nib Date: circa 1530 the protuberance of a mammary gland upon which in the female the lactiferous ducts open and from which milk is drawn, 2. an artificial teat through which a bottle-fed infant nurses, a device with an orifice through which the discharge of a liquid can be regulated, 3. a protuberance resembling or suggesting the ~ of a breast, a small projection through which oil or grease is injected into machinery, a pipe coupling consisting of a short piece of threaded tubing, ~d adjective