disadvantage vs mainstay

disadvantage

noun
  • Loss; detriment; hindrance. 

  • A setback or handicap. 

  • A weakness or undesirable characteristic; a con. 

verb
  • To place at a disadvantage. 

mainstay

noun
  • A chief support. 

  • Someone or something that can be depended on to make a regular contribution. 

  • A stabilising rope from the top of the mainmast to the bottom of the foremast. 

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