Plug. The interior piece of a cock.
Plug-and-collar gauge. A pair of gauges for the same size, the plug being sometimes termed the male and the collar the female gauge.
Plug-tap. A tap that follows the taper taps and has but two or three of its teeth eased off at the end.
Plumb-level. A levelling tool depending for its accuracy on a weighted line and an edge that is straight.
Plumb-rule. A straight edge containing a plumb-bob.
Pod-bit or nose-bit. A wood-boring tool, having a cutting lip at its end.
Point. The surface or the extremity of a gear-wheel tooth.
Polishing-lathe. A lathe that is used for polishing and therefore requires no tool-carrying devices.
Poppet-head. The main head of a lathe.
Porter-bar. A bar for handling heavy forgings, which is welded to the forging and afterwards cut off.