таємне підслуховування; приховане підслуховування
surreptitious listening device
surreptitious movement
surreptitious chemical weapons capability
surreptitious eavesdropping
surreptitious entry
surreptitious method
surreptitious operation
surreptitious smoking
surreptitious testing
listening post
listening silence
listening surveiilance
check for listening devices
underwater listening post
gaining information by use of listening posts
listening device
wall listening device
wall listening microphone
radio listening service
passive listening
passive listening device
air listening post