den vs glory hole

den

noun
  • A squalid or wretched place; a haunt. 

  • Synonym of fort (“structure improvised from furniture, etc. for playing games.”) 

  • A comfortable room not used for formal entertaining. 

  • A group of Cub Scouts of the same age who work on projects together. 

  • A small cavern or hollow place in the side of a hill, or among rocks; especially, a cave used by a wild animal for shelter or concealment. 

verb
  • To ensconce or hide oneself in (or as in) a den. 

glory hole

noun
  • A generally untidy place. 

  • An especially good place to fish, a particularly rich fishing spot. 

  • A bell-mouth spillway: a spillway (a structure in the reservoir above a dam that allows overflowing water to be released in a controlled fashion) that is shaped like an upside-down bell, thereby giving the appearance of a hole in the surface of the water. 

  • A hole in a mineshaft where an orebody is mined upwards until it breaks through the surface into the open air. 

  • A military trench. 

  • A deep built-in cupboard under the eaves or stairs of a house used for general storage, particularly of unrelated or unwanted items stored in some disorder. 

  • The stokehold on a coal-burning tramp steamer. 

  • An excavation into the sea floor designed to protect the wellhead equipment installed at the surface of a petroleum well from icebergs or pack ice. 

  • The stewards' mess on a passenger liner. 

  • A hole in a screen or wall big enough to allow an erect penis to be stuck through, made to facilitate anonymous sex with another person. 

  • A hole in the side of a furnace used to heat glass held on a metal rod. 

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