D defs.my
Entry 1 sense Webster, 1913

Observation post

· Ob·ser·va·tion post · IPA
01 a military outpost, usually at a height above the surrounding terrain, at or near the front line of a battle from which an observer may see…
  1. 1.
    a military outpost, usually at a height above the surrounding terrain, at or near the front line of a battle from which an observer may see the enemy's positions and direct artillery fire.(Mil.)