Room call waiting' is a service offered by some hotels and other establishments that allows guests to be notified when their room is ready. It involves the guest providing their contact information to the hotel, who will then call or text them when their room is ready. This service is often used by those who are arriving at a hotel before check-in time, as it allows them to go about their day without having to wait in the lobby for their room to be ready. The crossword solution for this term is NEXT, which is an acronym for 'Notify Everyone X-Time'.