emit vs secrete

emit

verb
  • To send out or give off. 

  • To come out, to be sent out or given off. 

secrete

verb
  • To exude or yield. 

  • To extract a substance from blood, sap, or similar to produce and emit waste for excretion or for the fulfilling of a physiological function. 

  • To conceal. 

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