What is "dead drop"

n. (context espionage English) A location used to secretly pass items between two people, without requiring them to meet.

n. a drop used for the clandestine exchange of intelligence information; "a dead drop avoids the need for an intelligence officer and a spy to be present at the same time"

A dead drop or dead letter box is a method of espionage tradecraft used to pass items or information between two individuals (e.g., a case officer and agent, or two agents) using a secret location, thus not requiring them to meet directly and thereby maintaining operational security. The method stands in contrast to the live drop, so-called because two persons meet to exchange items or information.