dish towel vs dishrag

dish towel

noun
  • A piece of absorbent cloth for drying or wiping dishes, cups or silverware 

  • A piece of cloth similar in size or texture, but used for other functions 

dishrag

noun
  • A piece of cloth used for washing dishes. 

  • An unclean person; used in similes. 

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