eavesdropping
v. B2 Upper Intermediate US //ˈivzˌdɹɑpɪŋ// UK //ˈiːvzdɹɒpɪŋ// eaves·drop·ping
v. to listen secretly to a private conversation without the people talking knowing you are there. You do this to find out a secret or a surprise.
v. to listen to a private conversation without the knowledge of the participants. Often used in the context of espionage or casual social observation.
He was caught eavesdropping on his neighbor's phone call.
The detective spent weeks eavesdropping on the suspects to gather enough evidence for the trial.
While professional eavesdropping is a serious crime, casual observers often do it to catch a glimpse of private conversations in public spaces.
From eavesdrop + -ing.