I. ˈyō-(ˌ)yō noun
( plural yo-yos )
Etymology: probably from Ilocano yóyo, or a cognate word in a language of the Philippines
Date: 1915
1. : a thick grooved double disk with a string attached to its center axle that is made to fall and rise to the hand by unwinding and rewinding on the string
2. : a condition or situation marked by regular fluctuations from one extreme to another
3. : a stupid or foolish person
II. adjective
Date: 1932
: shifting back and forth or up and down uncertainly or unexpectedly
III. intransitive verb
( yo-yoed ; yo-yo·ing )
Date: 1967
: to move from one position to another repeatedly : fluctuate
the stock price yo-yo ed