rollercoaster vs seesaw

rollercoaster

noun
  • Any situation in which there are ups and downs, or violent changes. 

  • An amusement ride consisting of a buggy on a track that rises, falls, twists and turns. 

seesaw

noun
  • A series of up-and-down movements. 

  • An abnormal breathing pattern caused by airway obstruction, characterized by paradoxical chest and abdominal movement. 

  • A structure composed of a plank, balanced in the middle, used as a game in which one person goes up as the other goes down. 

  • A series of alternating movements or feelings. 

verb
  • To cause to move backward and forward in seesaw fashion. 

  • To use a seesaw. 

  • To fluctuate. 

adj
  • fluctuating. 

How often have the words rollercoaster and seesaw occurred in a corpus of books? (source: Google Ngram Viewer )