An arbor is a cylinder affixed to a shaft. It is usually used as a spacer, to prevent side-to-side movement of the shaft, or part of a slip clutch. The arbor is usually affixed to the shaft by means of a set screw, or may be keyed.

Ar"bor (#), n. [OE. herber, herbere, properly a garden of herbs, F. herbier, fr. L. herbarium. See Herb, and cf. Herbarium.]

A kind of latticework formed of, or covered with, vines, branches of trees, or other plants, for shade; a bower.

Sir P. Sidney.

© Webster 1913.

Ar"bor, n. [Written also arbour.] [L., a tree, a beam.]

1. Bot.

A tree, as distinguished from a shrub.

2. [Cf. F. arbre.] Mech. (a)

An axle or spindle of a wheel or opinion.

A mandrel in lathe turning.

Knight.

Arbor Day, a day appointed for planting trees and shrubs. [U.S.]

© Webster 1913.