Yoyo

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.
something that fluctuates or moves up and down, especially suddenly or repeatedly.
slang. a stupid, foolish, or incompetent person.
informal. moving up and down or back and forth; fluctuating; vacillating:
yo-yo prices; a yo-yo foreign policy.
informal. to move up and down or back and forth; fluctuate or vacillate:
mortgage rates are still yo-yoing.
informal. to cause to yo-yo.
noun (pl) -yos
a toy consisting of a spool attached to a string, the end of which is held while it is repeatedly spun out and reeled in
(us & canadian, slang) a stupid person, esp one who is easily manipulated
verb (intransitive) yo-yos, yo-yoing, yo-yoed
(informal) to change repeatedly from one position to another; fluctuate
adjective
(informal) changing repeatedly; fluctuating
n.
you’re on your own