Abatis

{ Ab″a‐tis, Aba″t‐tis, } (ăb″ȧ‐tĭs; French ȧ′bȧ′tē″) n. [F. abatis, abattis, mass of things beaten or cut down, fr. abattre. See Abate.] (Fort.) A means of defense formed by felled trees, the ends of whose branches are sharpened and directed outwards, or against the enemy.