biological clock


Definition of biological clock

: an inherent timing mechanism in a living system that is inferred to exist in order to explain the timing or periodicity of various behaviors and physiological states and processes

Examples of biological clock in a Sentence

Recent Examples on the Web

This may have to do with your body's circadian rhythms, also know as your biological clock. Samantha Lauriello,, "This Is the Best Temperature for Sleeping, According to Experts," 9 July 2019 Three years ago the government ran an advertising campaign informing women that their biological clocks were ticking, as though this had not occurred to them. The Economist, "Why Germany’s birth rate is rising and Italy’s isn’t," 29 June 2019 In some cases, the researchers tinkered with the dinoflagellates’ internal biological clocks, to rob them of their ability to glow during the experimental period. The Economist, "The bioluminescence people find so attractive is a defence mechanism," 21 June 2019 The later start would better align with their biological clocks and allow students to get more sleep, Beresford said, both of which research has shown is critical to teenagers. Emma Kate Fittes, Indianapolis Star, "Carmel is considering changing school start times. Here's when students would start.," 14 June 2019 Recent studies show that many types of animals have biological clocks finely tuned to the cycles of the moon, which drives fascinating and sometimes bizarre patterns of behavior. Douglas Main, National Geographic, "Why oysters close on the full moon—and more odd lunar effects on animals," 17 Apr. 2019 The cause is unknown, but cluster headaches may occur if something with the body’s biological clock is off, per the Mayo Clinic. Amy Marturana, SELF, "What Your Headaches Can Tell You About Your Health," 29 Dec. 2018 In the days after daylight saving time starts, our biological clocks are a little bit off. Brian Resnick, Vox, "Daylight saving time ends Sunday: 8 things to know about “falling back”," 2 Nov. 2018 The timetable of how her life unfolds need not adhere to a pesky biological clock. Robin Marantz Henig, WIRED, "Women May Have an Alternative to Freezing Their Eggs," 27 Mar. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'biological clock.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of biological clock

1941, in the meaning defined above

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Last Updated

13 Jul 2019

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Time Traveler for biological clock

The first known use of biological clock was in 1941

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More Definitions for biological clock

biological clock


English Language Learners Definition of biological clock

: a system in the body that controls the occurrence of natural processes (such as waking, sleeping, and aging)

biological clock


Medical Definition of biological clock

: an inherent timing mechanism in a living system (as a cell) that is inferred to exist in order to explain various cyclical behaviors and physiological processes

More from Merriam-Webster on biological clock Encyclopedia article about biological clock

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