ague vs rigor

ague

noun
  • An intermittent fever, attended by alternate cold and hot fits. 

  • The cold fit or rigor of the intermittent fever 

  • A chill, or state of shaking, as with cold. 

verb
  • To strike with an ague, or with a cold fit. 

rigor

noun
  • A feeling of cold with shivering accompanied by a rise in body temperature. 

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