pendulum

pen·du·lum

noun \-ləm\

Definition of PENDULUM

1

: a body suspended from a fixed point so as to swing freely to and fro under the action of gravity and commonly used to regulate movements (as of clockwork)

2

: something (as a state of affairs) that alternates between opposites

Origin of PENDULUM

New Latin, from Latin, neuter of pendulus

First Known Use: 1660

Other Mechanical Engineering Terms

centrifuge, differential, flange, lathe, linchpin, pinion, plenum, ratchet, traction

pendulum

noun    (Concise Encyclopedia)

Body suspended from a fixed point so that it can swing back and forth under the influence of gravity. A simple pendulum consists of a bob (weight) suspended at the end of a string. The periodic motion of a pendulum is constant, but can be made longer or shorter by increasing or decreasing the length of the string. A change in the mass of the bob alone does not affect the period. Because of their constancy, pendulums were long used to regulate the movement of clocks. Other, special kinds of pendulums are used to measure the value of g, the acceleration due to gravity, and to show that the earth rotates on its axis (see Foucault pendulum).