Of, relating to, causing, or characterized by rotation, especially around an axis.


A part or device that rotates around an axis.

Rotating; turning round and round, as a wheel on its axis; having or characterized by rotation: as, rotary animalcules; rotary motion.

Acting or held in rotation, as officers or an office; turn-about; rotating.

In metal-working, a serrated rotary steel tool used on a mandrel in a lathe for operating upon a piece of metal presented to it and fed toward it on a slide-rest or other analogous movable support.

In wood-working: A rotary chisel-edged cutter fastened to a cutter-head, or one of a gang of cutters so attached, used to cut away superfluous wood in shaping irregular forms, as in the manufacture of hames for harness, of fellies for wagon-wheels, of curved chair-legs, etc. A solid steel tool having rotating cutting edges, in the nature of a burring-tool or router, used in carving-machines for cutting ornamental figures in intaglio. In working upon wood with rotary cutters, the cutter-head shafts or cutter-spindles are sometimes carried by movable bearings, and guided after the manner of a tracing-point or stylus in a pantograph. In other machines the bearings of the cutter-head shafts or spindles are stationary, and the work is itself guided and moved to produce the required shape or pattern. See bur, 4 , and router. Compare also shaper and shaping-machine.

A valve which makes complete and successive revolutions, thus alternately bringing its port or ports into continuity and discontinuity with a port or ports in its seat. This kind of valve has been but little used.


In electricity, a rotary converter.


Turning, as a wheel on its axis; pertaining to, or resembling, the motion of a wheel on its axis; rotatory.