The "internal body clock" that regulates the (roughly) 24-hour cycle of biological processes in animals and plants.

A method of natural birth control that involves counting days of a woman's menstrual cycle in order to determine when sexual intercourse is most or least likely to result in pregnancy.

plural of rhythm method

plural of rhythm game

(video games) A game that challenges the player to press buttons etc. to match a timed sequence indicated on the screen, usually in order to make the game character perform music or dance moves.

(poetry) rhyme royal

plural of battle rhythm

plural of circadian rhythm

A daily routine or order of business, especially as assumed by a military organization or during crisis.

plural of Lombardic rhythm