ABATIS

n. barricade made of felled trees placed one on top of the other with their branches pointing out toward the enemy

Abatis, abattis, or abbattis (a French word meaning a heap of material thrown) is a term in field fortification for an obstacle formed of the branches of trees laid in a row, with the tops directed towards the enemy. The trees are usually interlaced or tied with wire. Abatis are used alone or in combination with wire entanglements and other obstacles.
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Noun
1. line of defense consisting of a barrier of felled or live trees with branches (sharpened or with barbed wire entwined) toward the enemy
(synonym) abattis
(hypernym) line of defense, line of defence

v. demolish, tear down; fell, chop down (a tree); shoot down, cause an aircraft to fall; lower, drop; depress, make sad; humiliate, degrade

n. abatis, barricade made of felled trees placed one on top of the other with their branches pointing out toward the enemy