CAMP-ON

noun (Business World) (Science and Technology) A facility of electronic telephone systems which allows an unsuccessful caller to 'latch on' to a number so that the call is automatically connected once the receiving number is available. Etymology: The noun is formed on the verbal phrase to camp on to, which in turn is a figurative use of the verb to camp: the caller stakes claim to a place in the queue, and this 'pitch' is automatically registered by the system. History and Usage: First used in the mid seventies, the camp-on became increasingly widespread with the rise in popularity of push-button electronic telephones during the eighties. A Thorn Ericsson PABX can provide over twenty aids to efficient communications. Here is one of them: Camp-on busy. An incoming call for an extension that is already engaged (busy)...can be 'camped' on to the engaged extension. Daily Telegraph 10 Mar. 1977, p. 2