abattis

n. abatis, 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) abatis
(hypernym) line of defense, line of defence

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

v. pull down, knock down, kill or destroy (animals); murder, butcher, slaughter, injure; break, discourage; dispatch, despatch; flatten, defeat; sew the edge of a seam down flat, place or set down; write down, put to print; crush, repress (riots)

(n.)
A means of defense formed by felled trees, the ends of whose branches are sharpened and directed outwards, or against the enemy.