If you phone in to a place, you make a telephone call to that place. He has phoned in to say he is thinking over his options
If you phone in an order for something, you place the order by telephone. Just phone in your order three or more days prior to departure
If you phone in sick, you telephone your workplace to say that you will not come to work because you are ill. On Monday I was still upset and I phoned in sick to work
If you phone in to a radio or television show, you telephone the show in order to give your opinion on a matter that the show has raised. Listeners have been invited to phone in to pick the winner
(Should we move() this sense?) to choose to deliver a message by telephone when etiquette demands the effort and respect conveyed by in person communication
A phone-in is a programme on radio or television in which people telephone with questions or opinions and their calls are broadcast. She took part in a BBC radio phone-in programme. a radio or television programme in which you hear ordinary people expressing opinions or asking questions over the telephone