yo-yo
UK: ˈjəʊ.jəʊ | US: ˈjoʊ.joʊ
n. a toy consisting of two discs connected by an axle, which spins up and down on a string when manipulated
n. (informal) a situation or thing that repeatedly fluctuates between states
vt. to move up and down or back and forth rapidly
The word "yo-yo" originates from the Ilocano language (Philippines), where "yóyo" referred to the toy. It was later popularized in English by the Duncan Toys Company in the 1920s. The reduplicative structure (repeating "yo") mimics the toy's back-and-forth motion, and the term may also reflect an exclamatory sound ("yo!") associated with play. The word’s spelling and meaning have remained consistent since its adoption into English.
The child played with his yo-yo for hours, mastering tricks like "walk the dog."
Stock prices have been yo-yoing unpredictably this week.
She yo-yoed between excitement and anxiety before the performance.
The yo-yo’s string snapped after too many aggressive throws.
His diet progress was a yo-yo—losing weight only to regain it months later.