[n] a cashbox with an adding machine to register transactions; used in shops to add up the bill
[n] a regulator (as a sliding plate) for regulating the flow of air into a furnace or other heating device
[n] an air passage (usually in the floor or a wall of a room) for admitting or excluding heated air from the room
[n] (computer science) memory device that is the part of computer memory that has a specific address and that is used to hold information of a specific kind
[n] the timbre characteristic of a certain range and manner of production of the human voice
[n] an official written record of names or events or transactions
[n] a book in which names and transactions are listed
[v] register in a public office or in a court of law; "file for divorce"; "file a complaint"
[v] enter into someone's consciousness; "Did this event register in your parents' minds?"
[v] indicate a certain reading; of gauges and instruments; "The thermometer showed thirteen degrees below zero"; "The gauge read `empty'"
[v] send by registered mail; "I'd like to register this letter"
[v] register to vote; "register for an election"
[v] manipulate the registers of an organ
[v] be aware of; "Did you register any change when I pressed the button?"
[v] show in one's face; "Her surprise did not register"
[v] record in writing; enter into a register
[v] register as a candidate for several parties