activate vs fatigue

activate

verb
  • To encourage development or induce increased activity; to stimulate. 

  • To organize or create a military unit or station. 

  • To bring a player back after an injury. 

  • To put a device, mechanism (alarm etc.) or system into action or motion; to trigger, to actuate, to set off, to enable. 

  • To render a substance radioactive. 

  • To hasten a chemical reaction, especially by heating. 

  • To render more reactive; excite. 

  • To remove the limitations of demoware by providing a license; to unlock. 

  • To render a molecule reactive, active, or effective in performing its function. 

  • To aerate in order to aid decomposition of organic matter. 

fatigue

verb
  • To tire or make weary by physical or mental exertion. 

  • To lose so much strength or energy that one becomes tired, weary, feeble or exhausted. 

  • To cause to undergo the process of fatigue. 

  • To wilt a salad by dressing or tossing it. 

  • To undergo the process of fatigue; to fail as a result of fatigue. 

noun
  • Weakening and eventual failure of material, typically by cracking leading to complete separation, caused by repeated application of mechanical stress to the material. 

  • A weariness caused by exertion; exhaustion. 

  • A menial task or tasks, especially in the military. 

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