discourage vs steam up

discourage

verb
  • To extinguish the courage of; to dishearten; to depress the spirits of; to deprive of confidence; to deject. 

  • To persuade somebody not to do (something). 

noun
  • Lack of courage 

steam up

verb
  • To become steamy. 

  • To become coated with condensation. To fog up. 

  • To bring (a steam boiler) up to working steam pressure. 

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