Eavesdropper :: Eavesdropper (n.) One who stands under the eaves, or near the window or door of a house, to listen; hence, a secret listener..
Eavesdropping :: Eavesdropping (n.) The habit of lurking about dwelling houses, and other places where persons meet fro private intercourse, secretly listening to what is said, and then tattling it abroad. The offense is indictable at common law..