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pen·du·lum (pĕnjə-ləm, pĕndyə-, pĕndə-)
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n.
1. A body suspended from a fixed support so that it swings freely back and forth under the influence of gravity, commonly used to regulate various devices, especially clocks. Also called simple pendulum.
2. Something that swings back and forth from one course, opinion, or condition to another: the pendulum of public opinion.

[New Latin, probably from Italian pendolo, pendulous, pendulum, from Latin pendulus, hanging; see PENDULOUS.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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