biorhythm

noun

bio·​rhythm ˈbī-ō-ˌri-t͟həm How to pronounce biorhythm (audio)
: an innately determined rhythmic biological process or function (such as sleep behavior)
also : the internal mechanism that determines such a process or function
biorhythmic
ˌbī-ō-ˈrit͟h-mik How to pronounce biorhythm (audio)
adjective

Examples of biorhythm in a Sentence

Recent Examples on the Web
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.
Here is the mayfly on my hand bringing itself into synch with my biorhythms. — John Kinsella, The New Yorker, 11 Dec. 2023 Its tone remains a bit distant, its pace a few clicks under what seems like the natural biorhythm of the play. — Sara Holdren, Vulture, 16 Nov. 2023

Word History

First Known Use

1913, in the meaning defined above

Time Traveler
The first known use of biorhythm was in 1913

Rhymes for biorhythm

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biorhythm
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“Biorhythm.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/biorhythm. Accessed 25 Mar. 2025.

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Medical Definition

biorhythm

noun
bio·​rhythm ˈbī-ō-ˌrit͟h-əm How to pronounce biorhythm (audio)
: an innately determined rhythmic biological process or function (as sleep behavior)
also : an innate rhythmic determiner of such a process or function
biorhythmic
ˌbī-ō-ˈrit͟h-mik How to pronounce biorhythm (audio)
adjective
biorhythmicity
-rit͟h-ˈmis-ət-ē How to pronounce biorhythm (audio)
noun
plural biorhythmicities

More from Merriam-Webster on biorhythm

Britannica.com: Encyclopedia article about biorhythm

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