#bunker__dugout  a fortification of earth; mostly or entirely below ground
  supertype:  munition__fortification  defensive structure consisting of walls or mounds built around a stronghold to strengthen it
  subtype:  foxhole__fox_hole__foxhole  a small dugout with a pit for individual shelter against enemy fire
  subtype:  funk_hole  dugout as a place of safe retreat (when in a funk)

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