biorhythm

noun

Etymology: Etymology tree Proto-Indo-European *gʷeyh₃-der. Ancient Greek βῐ́ος (bĭ́os) Ancient Greek βῐο- (bĭo-)der. English bio- Proto-Indo-European *ser-? Proto-Indo-European *srew- Proto-Indo-European *sru-dʰ-mo-s Proto-Hellenic *hrutʰmós Ancient Greek ῥῠθμός (rhŭthmós)bor. Latin rhythmusder. English rhythm English biorhythm First coined 1960, from bio- + rhythm.

1. Any cyclic biological or physiological pattern or activity.
2. Any of three sinusoidal graphs, normally plotted by a computer, containing a person's birthdate as an origin, that are claimed to provide meaningful information about emotional levels, physical energy levels, and mental or psychic sensitivity.

   “Gay Biorhythms. Be Sure, Be Safe. Biorhythms charted for 1 year. Graphs or calendar. For more information write GCN Box 706.”