bush league vs tepid

bush league

adj
  • Amateurish, unprofessional, unpolished, juvenile. 

  • Of inferior quality. 

noun
  • A professional sports association at the lower levels of minor league organization. 

  • A low-ranking or inferior level among groups, professions, organizations, etc. 

tepid

adj
  • Uninterested; exhibiting little passion or eagerness; lukewarm. 

  • Lukewarm; neither warm nor cool. 

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