Ancient Anglo-Saxon law punished eavesdroppers, who skulked in the eavesdrip of another's home, with a fine; the eavesdropper was also sometimes called the eavesdrop. Eavesdrop also means a small low visibility hole near the entrance to a building (generally under the eaves) which would allow the occupants to listen in on the conversation of people awaiting admission to the house. Typically this would allow the occupant to be prepared for unfriendly visitors.

Early telephone systems shared party lines which would allow the sharing subscribers to listen to each others' conversations. This was a common practice in rural America which resulted in many incidents and feuds.

Techniques

Eavesdropping can also be done over telephone lines (wiretapping), email, instant messaging, and other methods of communication considered private. (If a message is publicly broadcast, witnessing it is not considered eavesdropping.) VoIP communications software is also vulnerable to electronic eavesdropping via malware infections such as Trojan.

Etymology

The verb eavesdrop was originally a back-formation of the noun eavesdropper ("a person who eavesdrops") which was formed from the unrelated noun eavesdrop ("the dripping of water from the eaves of a house; the ground on which such water falls"). An eavesdropper was one who stood at the eavesdrop (where the water fell, i.e., near the house) so as to overhear what was said inside.

Verb

eavesdropping

1. Present participle of eavesdrop.

Wikipedia eavesdropping (plural eavesdroppings)

1. the action of the verb 'to eavesdrop'
2. listening secretly to the private conversations of others
3. (telecoms) the interception of electronic communications

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