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biorhythm

[bahy-oh-rith-uh m]
SEE MORE SYNONYMS FOR biorhythm ON THESAURUS.COM

noun

Physiology. an innate periodicity in an organism's physiological processes, as sleep and wake cycles.

Origin of biorhythm

First recorded in 1960–65; bio- + rhythm
Related formsbi·o·rhyth·mic, adjectivebi·o·rhyth·mic·i·ty [bahy-oh-rith-mis-i-tee] /ˌbaɪ oʊ rɪðˈmɪs ɪ ti/, nounbi·o·rhyth·mist, bi·o·rhyth·mi·cist, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019
British Dictionary definitions for biorhythm

biorhythm

noun

a cyclically recurring pattern of physiological states in an organism or organ, such as alpha rhythm or circadian rhythm; believed by some to affect physical and mental states and behaviour
Derived Formsbiorhythmic, adjectivebiorhythmically, adverb
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for biorhythm
n.

also bio-rhythm, 1960, from bio- + rhythm. Related: Biorhythmic.

Online Etymology Dictionary, © 2010 Douglas Harper
biorhythm in Medicine

biorhythm

[bī′ō-rĭð′əm]

n.

A biologically inherent cyclic variation or recurrence of an event or state, such as sleep cycles and circadian rhythms.
Related formsbi′o•rhyth′mic (-rĭð′mĭk) adj.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.
biorhythm in Science

biorhythm

[bī′ō-rĭð′əm]

A recurring biological process, such as sleep, that is controlled by the circadian rhythms of an organism. See more at circadian rhythm.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.