convulsion vs stagnation

convulsion

noun
  • An uncontrolled fit, as of laughter; a paroxysm. 

  • An intense, paroxysmal, involuntary muscular contraction. 

  • Violent turmoil. 

stagnation

noun
  • Inactivity. 

  • The state of being stagnant, without circulation. 

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