internal clock

noun

1. biological clock.

Word History and Origins

Origin of internal clock¹

First recorded in 1955–60

Example Sentences

My internal clock wherever I am just knows it’s 4 p.m. and I get a little sad.

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When it is bright, our internal clock feels we should be awake.

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Additionally, disruptions to the body's internal clock can affect astronaut's sleeping and eating cycles.

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Prof Luscher said that - like the researchers suggest - it is "possible" that coffee drinking later in the day could disrupt out bodies internal clock at a time we should be resting.

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You really have to be thoughtful of your act structures and that internal clock.

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