Abbreviation of year(s) old; also y.o., y/o. / (crochet) Initialism of yarn over.

(Baltimore) third-person singular, familiar

The letter Ё, ё.

Short for yoleven.

(African-American Vernacular) Alternative spelling of yo (non-rhotic pronunciation of your)

A series of failed diets that cause a person to lose and gain weight alternately.

(computing, slang) The condition of having repeated intermittent failures, such that the system alternates between being up and down.

plural of high yo-yo

(aviation, military) A dogfighting maneuver used to increase the closure rate of the attacker during a turn, involving the attacker temporarily giving up some altitude to simultaneously increase airspeed and allow them to turn more steeply, enabling the attacker to cut across the defender's turn and catch up with the defender.

plural of low yo-yo