1 (C) a polite or formal demand for something(+ for): They have made an urgent request for international aid. | request that: He ignored the neighbours' requests that he should make less noise. | at sb's request (=because they asked you to): I telephoned her in Paris, at Staunton's request. | on request (=when you ask for it): Further details will be sent on request. | by request (=because someone has especially asked for it): There were no flowers at the funeral, by request. | any requests? spoken (=used to ask people if they want anything): I'm going to the bar - any requests?2 (C) a piece of music that is played on the radio because someone has asked for it2 verb (T)1 formal to ask for something politely or formally: I wrote them a letter, officially requesting permission to proceed. | request that: The staff immediately requested that he reconsider his decision. | request sb to do sth: All club members are requested to attend the annual meeting.2 to ask for a particular piece of music to be played on the radio: This song was requested by Mrs Simpson of Potters Bar.USAGE NOTE: REQUEST WORD CHOICE: ask (for), request, demand Ask is the usual word for speaking or writing to someone in order to get something done: I asked one of my friends to help me. You use ask for when you are trying to get something: I asked for help. Request is more formal and official. Also if you request something, often you have the right to get what you are asking for: The letter politely requested that Miss Willis present herself for interview the next day. | The government has requested a meeting with community leaders. Demand is even stronger. If you demand something, you feel strongly that you have the right to it: I demand to see the manager! GRAMMAR You request something (NOT request for sth). But you do use for with the noun: requests for money (NOT requests of money).
Longman dictionary of contemporary English. 2004.