# pendulum

/ˈpɛndʒəɫəm/ (US) · /pˈɛndjʊləm/ (UK) · CEFR B2 · Noun

Source: https://englishreference.com/word/pendulum
Updated: 2026-05-07

## Definition

a weight that hangs from a fixed point and swings back and forth. You often see this in old clocks or used as a symbol for changing opinions.

For teachers: a body suspended from a fixed point so as to swing freely to and fro under the action of gravity. Frequently used metaphorically to describe a situation that oscillates between two extremes.

## Examples

- The heavy pendulum in the old clock swings steadily.
- Public opinion is like a pendulum, swinging from one political extreme to the other every few years.
- The physicist adjusted the length of the wire to ensure the pendulum maintained a consistent period, demonstrating the principles of simple harmonic motion to the students.

## Usage notes

- Often used in the phrase 'the pendulum swings' to describe a shift in mood, politics, or fashion.

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