biological clock

noun

: 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

And again, as if some biological clock were repeating its cloying chime, leading us brightly down the road to our collective intellectual doom. —Literary Hub, Literary Hub, 18 Nov. 2025

But as scientists have learned more about the importance of keeping our biological clocks in sync, society has moved in the opposite direction. —Allison Aubrey, NPR, 3 Nov. 2025

For these birds, the return of the sunlight signaled the start of a new day, effectively resetting their biological clocks, Aguilar said. —Ashley Strickland, CNN Money, 13 Oct. 2025

Williams notes that many successful women in their 30s and 40s also feel the biological clock ticking, which makes slowing down seem impossible. —Essence, 24 Sep. 2025

Word History

First Known Use

1941, in the meaning defined above

Rhymes for biological clock

• aftershock
• antiknock
• arawak
• hollyhock
• interlock
• isopach
• manioc
• shuttlecock
• tomahawk
• weathercock
• alcock
• beanstalk

Kids Definition

biological clock

noun

: a mechanism that exists in living things and controls the timing of behaviors and bodily functions which occur in cycles

Medical Definition

biological clock

noun

: 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