biorhythm

noun

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.”