Verb > Eavesdrop

Verb – Eavesdrop

(no object)

to listen secretly to what other people are saying — usually + on

He was eavesdropping (=listening in) on his sister and her friends in the next room.

She was accused of eavesdropping on private telephone conversations.

eavesdropper noun, plural eavesdroppers (count)

eavesdropping noun (noncount)

electronic eavesdropping