What is the meaning of the word "yo-yo"?

Definitions:

  1. a toy consisting of a spool that is reeled up and down on a string by motions of the hand copy to clipboard noun
    • My yoyo's string is broken. copy to clipboard
  2. to play with a yo-yo copy to clipboard verb
    • My nibling can yoyo with both hands at the same time. copy to clipboard