1911 Encyclopædia Britannica/Eavesdrip
EAVESDRIP, or Eavesdrop, that width of ground around a house or building which receives the rain water dropping from the eaves. By an ancient Saxon law, a landowner was forbidden to erect any building at less than 2 ft. from the boundary of his land, and was thus prevented from injuring his neighbour’s house or property by the dripping of water from his eaves. The law of Eavesdrip has had its equivalent in the Roman stillicidium, which prohibited building up to the very edge of an estate.
From the Saxon custom arose the term “eavesdropper,” i.e. any one who stands within “the eavesdrop” of a house, hence one who pries into others’ business or listens to secrets. At common law an eavesdropper was regarded as a common nuisance, and was presentable at the court leet, and indictable at the sheriff’s tourn and punishable by fine and finding sureties for good behaviour. Though the offence of eavesdropping still exists at common law, there is no modern instance of a prosecution or indictment.