barrier
bar.ri.er \'bar-e--*r\ n [ME barrere, fr. MF barriere, fr. barre] 1a: a
material object or set of objects that separates, demarcates, or serv es as
a barricade 1b: an extension of the antarctic continental ice sheet into
the sea restin g partly on the bottom pl, often cap 2: a medieval war game
in which combatants fight on foot with a fence or ra iling between them 3:
the movable gate or device at the starting line in a racetrack 4:
something immaterial that impedes or separates 5: a factor that tends to
restrict the free movement and mingling of indivu als or populations