internal clock

American  

noun

1. biological clock.

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Etymology

Origin of internal clock

First recorded in 1955–60

Example Sentences

See Examples For:

internal clock

However, it adds to growing evidence around chrononutrition, a field that looks at how the body's internal clock influences how food is processed.

From Science Daily ● May 1, 2026

Almost all cells in the body contain their own internal clock, which can be influenced by light, physical activity, and food timing.

From Science Daily ● Jan. 3, 2026

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

From Los Angeles Times ● Jul. 25, 2025

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

From BBC ● Apr. 16, 2025

Dad had jumbled my internal clock, thanks to our late-night marathon of Doctor Who—my favorite episodes with the brilliant and brave Martha Jones.

From "Sir Fig Newton and the Science of Persistence" by Sonja Thomas