no end vs plethora

no end

noun
  • A great amount. 

adv
  • Exceedingly; endlessly. 

plethora

noun
  • An excessive amount or number; an abundance. 

  • Excess of blood in the skin, especially in the face and especially chronically. 

How often have the words no end and plethora occurred in a corpus of books? (source: Google Ngram Viewer )