Pendulum

Pendulum, pen′dū-lum, n. any weight so hung from a fixed point as to swing freely: the swinging weight which regulates the movement of a clock: a lamp, &c., pendent from a ceiling: a guard-ring of a watch by which it is attached to a chain.—adj. Pen′dular, relating to a pendulum.—v.i. Pen′dulate, to swing, vibrate.—adjs. Pen′dulent, pendulous; Pen′duline, building a pendulous nest; Pen′dulous, hanging loosely: swinging freely, as the pensile nests of birds: (bot.) hanging downwards, as a flower on a curved stalk.—adv. Pen′dulously.—ns. Pen′dulousness, Pen′dulosity.—Pendulum wire, a kind of flat steel wire for clock pendulums.—Compensation pendulum, a pendulum so constructed that its rod is not altered in length by changes of temperature; Compound pendulum, every ordinary pendulum is compound, as differing from a Simple pendulum, which is a material point suspended by an ideal line; Invariable pendulum, a pendulum for carrying from station to station to be oscillated at each so as to fix the relative acceleration of gravity; Long and short pendulum, a pendulum for determining the absolute force of gravity by means of a bob suspended by a wire of varying length. [L., neut. of pendulus, hanging—pendēre, to hang.]