What does "nipple" mean?

Nipple: The orifice at which any animal liquid, as the oil from an oil bag, is discharged. [R.] Derham.

Additional senses

  1. 2.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.
  2. 3.(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.

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