overextend vs peter out

overextend

verb
  • To push a pawn too far, so that it becomes vulnerable to the opponent's attacks. 

  • To expand or extend to an excessive degree, especially to do so beyond a safe limit. 

  • To apply (a term) to too many referents, by overextension. 

peter out

verb
  • Synonym of peter (“originally (mining), of a vein of ore: to be depleted of ore; now (generally), to diminish to nothing; to dwindle, to trail off”) 

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