Eaves Dropping

What is the origin of Eves Dropping?

It's "eaves."

EAVESDROP - ".comes to us virtually unchanged from Anglo-Saxon days. In those times a house had very wide overhanging eaves, not unlike those that may still be seen on thatched cottages in Devon. Since rain gutters and spouts were unknown then, the purpose of the wide overhang was to allow rain to drip safely away from the house's foundation. So the 'eavesdrip,' which later became 'eavesdrop,' provided a sheltered place where one could hide to listen clandestinely to conversations within the house." From Morris Dictionary of Word and Phrase Origins by William and Mary Morris (HarperCollins, New York, 1977, 1988).