hangup

Hang up is a common phrasal verb meaning to end a telephone call by removing the handset or disconnecting the line. In everyday use, to hang up a call signifies finishing the conversation and releasing the connection. The term is also used more loosely to indicate the end of a communication session in various technologies.

Historically, the phrase derives from traditional landline telephones, where placing the receiver back on its cradle physically disconnected the circuit. The action of hanging the phone up became a natural metaphor for terminating a communication.

In computing and telecommunications, hang up can refer to the act of disconnecting a device or session. In Unix-like operating systems, the SIGHUP signal indicates that the controlling terminal has been closed, and the associated process may terminate or reload its configuration. In telephony, a call hang-up occurs when one party disconnects or the network ends the session. In call centers and similar environments, the term hang-up rate describes the proportion of calls terminated before a meaningful interaction occurs.

Psychologically or socially, "hang-up" can describe an obstacle or fixation. A person may have a hang-up about a particular issue, meaning an impediment to progress or an irrational reluctance. The term is frequently used both in literal contexts related to telephony and in figurative discussions of personal or organizational barriers.

See also: SIGHUP, call termination, telecommunication.