- 1[uncountable] the telephone number of the service that you use to find out a person's telephone number Call 411.
- 2 the 411 [singular] (informal) the true facts about a situation or the information you need He'll give us the 411 on what to expect. Do you have the 411? Anyone got the 411 on when the next shipment will be?
NAmE//ˌfɔr wʌn ˈwʌn//