·noun Any limit or boundary; a line of separation.
II. Barrier ·noun An any obstruction; anything which hinders approach or attack.
III. Barrier ·noun A fence or railing to mark the limits of a place, or to keep back a crowd.
IV. Barrier ·noun A fortress or fortified town, on the frontier of a country, commanding an avenue of approach.
V. Barrier ·noun A carpentry obstruction, stockade, or other obstacle made in a passage in order to stop an Enemy.