-ləm noun
( -s )
Usage: often attributive
Etymology: New Latin, from Latin, neuter of pendulus hanging, pendent
1.
a. : 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 the movements of clockwork and other machinery
b. : a suspended body that vibrates not by swinging but by rotating, with alternate twisting and untwisting (as the balance wheel of a watch) — called also torsion pendulum
2. : something that alternates between opposites
the pendulum of public opinion
3. : a technique used in mountain climbing to accomplish a difficult traverse by swinging across on a rope