barbican vs guard station

barbican

noun
  • A temporary wooden tower built for defensive purposes. 

  • 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 tower at the entrance to a castle or fortified town 

  • A fortress at the end of a bridge. 

guard station

noun
  • Synonym of guardhouse. 

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