barbican vs berm

barbican

noun
  • A tower at the entrance to a castle or fortified town 

  • An opening in the wall of a fortress through which the guns are levelled; a narrow loophole through which arrows and other missiles may be shot. 

  • A fortress at the end of a bridge. 

  • A temporary wooden tower built for defensive purposes. 

berm

noun
  • A ledge between the parapet and the moat in a fortification. 

  • A raised bank or path, especially the bank of a canal opposite the towpath. 

  • A mound or bank of earth, used especially as a barrier or to provide insulation. 

  • A terrace formed by wave action along a beach. 

  • A strip of land between a street and sidewalk. 

  • Edge of a road. 

  • A narrow ledge or shelf, as along the top or bottom of a slope. 

verb
  • To provide something with a berm 

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