barbican vs rampart

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. 

rampart

noun
  • A defensive structure; a protective barrier; a bulwark. 

  • A defensive mound of earth or a wall with a broad top and usually a stone parapet; a wall-like ridge of earth, stones or debris; an embankment for defensive purpose. 

  • That which defends against intrusion from outside; a protection. 

  • A steep bank of a river or gorge. 

verb
  • To defend with a rampart; fortify or surround with a rampart. 

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