listening post

Military. a post or position, as in advance of a defensive line, established for the purpose of listening to detect the enemy's movements.

any foreign country or city viewed as a source of intelligence about an enemy or rival nation or one that is a potential enemy.

any concealed position maintained to obtain information: The government had listening posts to keep informed of revolutionary activities.

Origin of listening post

First recorded in 1915–20

The young officer in command of the listening-post cursed softly.

Italy at War and the Allies in the West |E. Alexander Powell
An English private soldier was detailed to go on listening-post with me.

Private Peat |Harold R. Peat
That night the Sergeant came along and said, "Goddard and Wilson, go out on listening-post."

Into the Jaws of Death |Jack O'Brien
I'm going on listening-post to-night, and I shouldn't wonder if we get it pretty hot.

With Haig on the Somme |D. H. Parry

I can frankly say I disliked the listening-post duty that first time.

Private Peat |Harold R. Peat

listening post

military a forward position set up to obtain early warning of enemy movement Abbreviation: LP

any strategic position or place for obtaining information about another country or area