Nip"ple (?), n. [Formerly neble, a dim. of neb. See Neb, Nib.]
1. (Anat.) The protuberance through which milk is drawn from the breast or mamma; the mammilla; a teat; a pap.
2. The orifice at which any animal liquid, as the oil from an oil bag, is discharged. [R.]Derham.
3. Any small projection or article in which there is an orifice for discharging a fluid, or for other purposes; as, the nipple of a nursing bottle; the nipple of a percussion lock, or that part on which the cap is put and through which the fire passes to the charge.
4. (Mech.) A pipe fitting, consisting of a short piece of pipe, usually provided with a screw thread at each end, for connecting two other fittings.Solder nipple, a short pipe, usually of brass, one end of which is tapered and adapted for attachment to the end of a lead pipe by soldering.Page 977
The noun Nipple has 2 senses
1. nipple -- a flexible cap on a baby's feeding bottle or pacifier
2. nipple, mammilla, mamilla, pap, teat, tit -- the small projection of a mammary gland