800 Number Definition
noun
A toll-free telephone number, specif. one with an 800, 866, 877, etc. prefix.
Webster's New World
Name given to toll-free telephone numbers in North America.
Wiktionary
Other Word Forms of 800 Number
Noun
Singular:
800 number
Plural:
800-numbersOrigin of 800 Number
In the original North American Numbering Plan, phone numbers beginning with an area code of "800" were reserved for so called toll-free numbers, where the party receiving the call pays the charges. As more toll-free numbers were needed, additional area codes were added to the scheme including 888, 877, 866, and four more were reserved: 8555, 8444, 8333 and 8222. The term "800 Number" is used colloquially to refer to all of these.
From Wiktionary
