exigency vs plethora

exigency

noun
  • The demands or requirements of a situation. 

  • An urgent situation, one requiring extreme effort or attention. 

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 exigency and plethora occurred in a corpus of books? (source: Google Ngram Viewer )