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biorhythmics

American  
[bahy-oh-rith-miks] / ˌbaɪ oʊˈrɪð mɪks /

noun

(used with a singular verb)
  1. the study of biorhythms.


biorhythmics British  
/ ˌbaɪəʊˈrɪðmɪks /

noun

  1. (functioning as singular) the study of biorhythms

"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

Etymology

Origin of biorhythmics

biorhythm, -ics