abbreviated dialing

Abbreviated dialing is the use of a very short series of telephone numbers to reach public services. Typically these are two or three digits, and are most commonly known as being emergency telephone numbers like 1-1-2 and 9-1-1. Other services may also be available this way, such as the N11 codes in the NANP.
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A telephone service feature that (a) permits the user to dial fewer digits to access a network than are required under the nominal numbering plan, and (b) is limited to a subscriber -selected set of frequently dialed numbers. Synonym speed dialing .