hole up vs skulk

hole up

verb
  • To hide. 

  • To go into a hole, to shelter in a hole. 

skulk

verb
  • To stay where one cannot be seen, conceal oneself (often in a cowardly way or with the intent of doing harm). 

  • To avoid an obligation or responsibility. 

  • To move in a stealthy or furtive way; to come or go while trying to avoid detection. 

noun
  • The act of moving in a stealthy or furtive way. 

  • A stealthy or furtive gait or way of moving. 

  • A group of people seen as being fox-like (e.g. cunning, dishonest, or having nefarious plans). 

  • A group of foxes. 

  • The act of avoiding an obligation or responsibility. 

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