bio·​rhythm | \ ˈbī-ō-ˌri-t͟həm \

Definition of biorhythm 

: an innately determined rhythmic biological process or function (such as sleep behavior) also : the internal mechanism that determines such a process or function

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Other Words from biorhythm

biorhythmic \ ˌbī-​ō-​ˈrit͟h-​mik \ adjective

Examples of biorhythm in a Sentence

Recent Examples on the Web

Deutsche Lufthansa AG last year began using 24 different light settings on its Airbus A350-900 planes to help manage passenger biorhythms during long haul flights. Robert Wall, WSJ, "Airlines Conquer Challenges of Long-Haul Flights. Now Can Passengers?," 24 Mar. 2018

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

First Known Use of biorhythm

1913, in the meaning defined above

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Time Traveler for biorhythm

The first known use of biorhythm was in 1913

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More Definitions for biorhythm



English Language Learners Definition of biorhythm

: a natural, repeated pattern of changes that occur in the body and that affect the way a person feels


bio·​rhythm | \ ˈbī-ō-ˌrit͟h-əm \

Medical Definition of biorhythm 

: an innately determined rhythmic biological process or function (as sleep behavior) also : an innate rhythmic determiner of such a process or function

Other Words from biorhythm

biorhythmic \ ˌbī-​ō-​ˈrit͟h-​mik \ adjective
biorhythmicity \ -​rit͟h-​ˈmis-​ət-​ē \ noun, plural biorhythmicities

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involving abstract or general statements

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