barrier

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barrier

1. 
a. an exposed offshore sand bar separated from the shore by a lagoon
b. (as modifier): a barrier beach
2. that part of the Antarctic icecap extending over the sea

Barrier

 

(in Russian, zaval), an antitank, antitransport, or anti-infantry obstacle. Barriers are made of lumber, stones, or snow on probable enemy routes of travel in places where it is difficult to bypass them. When setting up a timber barrier, trees of more than 20 cm in diameter are used. They are sawed down at a height of 60–120 cm and piled criss-cross with the crowns facing the enemy. In order to make it difficult to pull the barrier apart, the trees are not completely separated from their stumps; they are secured to them, woven with barbed wire, and also reinforced by the placement of land mines and high-explosive charges. During the Great Patriotic War of 1941–45 timber barriers were used extensively by Soviet troops on the defense in forested regions. Stone barriers are set up in mountains or in populated areas by demolishing cliffs or urban stone structures. Barriers made of snow can be devised in mountain and northern regions. In mining the Russian word zaval signifies the accidental destruction of a large rock mass in a mining excavation that disrupts its normal use.


Barrier

 

a lifting or sliding beam, usually installed at a railroad crossing to stop automobile, cart, and pedestrian traffic prior to the passing of a train. Barriers may be operated manually, mechanically, or automatically. Automatic barriers are operated by signals from the railroad’s automation and remote control systems; signal lights and acoustic devices may be used. The normal position for automatic barriers is the open position; for nonauto-matic barriers it is the closed position.

What does it mean when you dream about a barrier?

A barrier may signify that the dreamer is experiencing some obstacle in an arena of his or her life.

barrier

[′bar·ē·ər]
(ecology)
Any physical or biological factor that restricts the migration or free movement of individuals or populations.
(navigation)
Anything which obstructs or prevents passage of a craft.
(physics)

Barrier

[′bar·ē·ər]
(ordnance)
A passive acoustic detection system for submarines, consisting of hydrophones positioned on the ocean floor and connected by undersea cable to a land-based computer center.

barrier

1. Same as barricade.
2. According to the Architectural Barriers Act, any obstacle to the accessibility of a building by disabled people.

barrier

barrierclick for a larger image
i. As it relates to the sound barrier, it is a barrier to flight encountered by an airplane designed for subsonic speeds when it reaches transonic speeds and meets the turbulence incident of diverse degrees of compressibility. Intense buffet and loss of controls to a varying degree may be experienced at this speed.
ii. A net forming part of an arrester, or crash barrier system meant to arrest forward motion of an aircraft that is likely to overshoot the runway. Normally, the net lies horizontally on the ground and is raised when required. The vertical ropes of the barrier net are made of nylon, which are attached to the steel ropes at the top and the bottom of the barrier net.