1. a spoollike toy consisting of two thick wooden, plastic, or metal disks connected by a dowel pin in the center to which a string is attached, one end being looped around the player's finger so that the toy can be spun out and reeled in by wrist motion.
2. something that fluctuates or moves up and down, especially suddenly or repeatedly.
3. Slang. a stupid, foolish, or incompetent person. adjective
4. Informal. moving up and down or back and forth; fluctuating; vac
"markets can be yoyo."
"behaviours can be yoyo."
This list can help you learn new vocabulary more quickly and be able explore other words more easily.