bridgehead has definitions from the field of military
1
[ noun ] (military) an area in hostile territory that has been captured and is held awaiting further troops and supplies

Synonyms

beachhead foothold

Examples

"an attempt to secure a bridgehead behind enemy lines" "the only foothold left for British troops in Europe was Gibraltar"

Used in print

(Barry Goldwater, "A Foreign Policy for America"...)

One Latin_American country , Cuba , has become a Soviet bridgehead ninety miles off our coast .

Related terms

combat_zone beachhead airhead

2
[ noun ] a defensive post at the end of a bridge nearest to the enemy

Related terms

post

*