• (British) IPA: /ˈjəʊ.jəʊ/
• (America) IPA: /ˈjoʊ.joʊ/

yo-yo (plural yo-yos)

1. A toy consisting of a spheroidal or cylindrical spindle having a circular groove in which string is wound; it is used by holding the string in the fingers and reeling the spindle up and down by movements of the wrist.

   Coordinate terms: diabolo, whirligig

   I bought a yo-yo from the toy store yesterday.

2. (finance) A volatile market that moves up and down.
3. (informal) Someone who vacillates.
4. (aviation, military) A dogfighting maneuver involving the attacker temporarily exchanging altitude for airspeed, or vice versa, in order to rapidly catch up with the defender or to prevent an overshoot.
5. (sewing) A cloth rosette formed by gathering the outside edge of a circle of fabric in toward the centre using a running stitch.
6. (informal) A foolish, annoying or incompetent person.

   It is hard to watch the management for very long and not conclude that the place is run by a bunch of yo-yos.

• French: yo-yo
• German: Jo-Jo, Yo-Yo
• Italian: yo-yo
• Portuguese: ioiô
• Russian: йо-йо́
• Spanish: yo-yo, yoyó

• Portuguese: fuxico

yo-yo (yo-yos, present participle yo-yoing; simple past and past participle yo-yoed)

1. (intransitive) To vacillate; to move up and down.
   • 1990, The Economist, volume 316, page 93:

     The yo-yoing stockmarket whizzed back up by around a quarter and then started to fall again.