The nut that secures the end of a spoke to the rim of a bicycle wheel Nipples have a normal right-hand thread, but because they are normally seen from the "bolt" side, it is often confusing which way to turn them It is as if you were watching the hands of a clock move clockwise, but the clock was transparent, and you were looking from behind it Of all the things bicycle mechanics do, adjusting spoke nipples is the one that requires the most skill and experience If you wish to learn more about this process, see my article on Wheelbuilding
{i} tip of mammary gland of mammals; place out of which milk flows from the female breast; any nipple-shaped device (e.g. pacifier, bottle top, etc.); threaded projection for connecting pipes
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
The nipples on someone's body are the two small pieces of slightly hard flesh on their chest. Babies suck milk from their mothers' breasts through their mothers' nipples. Sore nipples can inhibit the milk supply