ideation vs rumination

ideation

noun
  • The conceptualization of a mental image. 

  • The synthesis of ideas. 

rumination

noun
  • Deep thought or consideration. 

  • The act of ruminating; i.e. chewing cud. 

  • Negative cyclic thinking; persistent and recurrent worrying or brooding. 

  • An eating disorder characterized by repetitive regurgitation of small amounts of food from the stomach. 

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