dawdler vs idler

dawdler

noun
  • A person who dawdles or idles. 

idler

noun
  • One who idles; one who spends his or her time in inaction. 

  • One who idles; a lazy person; a sluggard. 

  • A mechanical device such as a pulley or wheel that does not transmit power, but supports a moving belt etc. 

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