internal clock
noun
1
: a system in the body that controls when a person needs to sleep, eat, etc.
The long trip upset my internal clock and I had a hard time getting to sleep.
2
: a clock or timing device that is inside a computer
Examples of internal clock in a Sentence
Recent Examples on the Web
Melatonin is a popular over-the-counter sleep supplement that helps regulate your body's internal clock, or circadian rhythm.
—
Ayesha Gulzar, Verywell Health, 21 Jan. 2026
The sleepy cues are managed by your circadian rhythm, or your body's internal clock.
—Andee Tagle, NPR, 15 Jan. 2026
The body's internal clock influences many processes, including digestion, hormone release and metabolism, according to research.
—Khloe Quill, FOXNews.com, 22 Dec. 2025
Your circadian rhythm is your body’s internal clock.
—Gina Park, CNN Money, 8 Dec. 2025
See All Example Sentences for internal clock
Examples are automatically compiled from online sources to
show current usage.
Read More
Opinions expressed in the examples do not represent those of Merriam-Webster or its editors.
Send us feedback.
Ayesha Gulzar, Verywell Health, 21 Jan. 2026
The sleepy cues are managed by your circadian rhythm, or your body's internal clock.
—Andee Tagle, NPR, 15 Jan. 2026
The body's internal clock influences many processes, including digestion, hormone release and metabolism, according to research.
—Khloe Quill, FOXNews.com, 22 Dec. 2025
Your circadian rhythm is your body’s internal clock.
—Gina Park, CNN Money, 8 Dec. 2025
See All Example Sentences for internal clock
Cite this Entry
“Internal clock.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/internal%20clock. Accessed 29 Jan. 2026.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
