merry-go-round vs yo-yo

merry-go-round

noun
  • A piece of playground equipment consisting of a circular platform that is made to revolve by pushing while users stand on it. 

  • A meaningless cycle; a bustle of activity that gets nowhere 

  • A series of singles and doubles that allow the batting team to score while still having runners on base who can be driven in by the next batter. 

  • A carousel; a pleasure ride, typically found at fairs and amusement parks, consisting of a slowly revolving circular platform on which various seats are fixed, frequently shaped like horses or other animals. 

  • A freight train of hopper wagons which loads and unloads its cargo while moving, a balloon loop being provided at power stations. 

  • A cooperative scheme in which members regularly contribute money to a pool, and the collected money is then paid out to one of the members, repeating so that every member has eventually received the collected money. 

yo-yo

noun
  • 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. 

  • A cloth rosette formed by gathering the outside edge of a circle of fabric in toward the centre using a running stitch. 

  • Someone who vacillates. 

  • 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. 

  • A volatile market that moves up and down. 

  • A foolish, annoying or incompetent person. 

verb
  • To vacillate; to move up and down. 

How often have the words merry-go-round and yo-yo occurred in a corpus of books? (source: Google Ngram Viewer )