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
Support Natural Circadian Rhythm When traveling across three or more time zones, your circadian rhythm (your 24-hour internal clock) can't immediately adjust to the new time zone's light-dark cycle, resulting in jet lag.
—
Anna Giorgi, Verywell Health, 6 May 2026
Morning light is the single most powerful signal your body uses to set its internal clock, sleep specialists say.
—Samantha Agate, Fort Worth Star-Telegram, 6 May 2026
Some research suggests that eating outside of regular daytime hours may disrupt the body’s internal clock.
—Lindsey Desoto, Health, 30 Apr. 2026
Even one or two late nights can throw your body’s internal clock off for days.
—Allison Palmer, Charlotte Observer, 16 Apr. 2026
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.
Anna Giorgi, Verywell Health, 6 May 2026
Morning light is the single most powerful signal your body uses to set its internal clock, sleep specialists say.
—Samantha Agate, Fort Worth Star-Telegram, 6 May 2026
Some research suggests that eating outside of regular daytime hours may disrupt the body’s internal clock.
—Lindsey Desoto, Health, 30 Apr. 2026
Even one or two late nights can throw your body’s internal clock off for days.
—Allison Palmer, Charlotte Observer, 16 Apr. 2026
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 10 May. 2026.
Copy CitationLove words? Need even more definitions?
Merriam-Webster unabridged
