sit back vs slummock

sit back

verb
  • To relax, to not exert oneself. 

  • To recline while still in a seated position, with one's back on the frame of the seat. 

slummock

verb
  • To behave lazily or indolently 

  • To behave awkwardly or clumsily 

noun
  • A slovenly person 

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