埋伏下来等待发动袭击
to hide and wait for someone in order to attack them
The soldiers lay in ambush, their guns loaded.
They marched into the valleys to lie in ambush near the roads.
His weapons had been taken by someone who must have been lying in ambush nearby.
The waited in ambush, then surrounded the traitors on the bridge.
We entered the room warily, worried the enemy might be waiting in ambush.
See also: ambush noun