1.(Fort.) A carpentry obstruction, stockade, or other obstacle made in a passage in order to stop an enemy.
2.A fortress or fortified town, on the frontier of a country, commanding an avenue of approach.
3.pl. A fence or railing to mark the limits of a place, or to keep back a crowd. "No sooner were the barriers opened, than he paced into the lists."
4.Any obstruction; anything which hinders approach or attack. "Constitutional barriers."
5.Any limit or boundary; a line of separation. "'Twixt that (instinct) and reason, what a nice barrier!"
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