A thin opening or groove, especially one in a door or wall. Also, a position or time in which something happens or is scheduled to happen. “They slotted their appointment for four o’clock”

A space in the schedule for a meeting or event. “The conference’s time slots are all full, but we can still hold the meeting in this room.”

In computing, a “slot” is an operation issue and data path machinery surrounding a set of execution units. In very long instruction word (VLIW) computers, the concept is similar to a pipeline.

An identifying number or letter on a piece of equipment, such as a computer chip or a card reader. Also, the position in which an object or person fits into a machine. “The card reader has a three-position slot for cards.”

In casinos, a slot is the area in which money is placed. A player inserts cash or, in ticket-in, ticket-out machines, a barcoded paper ticket with a magnetic stripe or microchip. Then, the machine activates a series of reels that spin and stop to rearrange symbols. If the symbols match a winning combination on the paytable, the player receives credits according to the machine’s settings.

Modern electromechanical slot machines have many possible combinations of symbols, but manufacturers limit jackpot sizes by assigning weight to specific symbols. Electronic machines can also detect when a slot is tilted or otherwise tampered with, triggering an alarm. Although tilt is now a technical term for any kind of error, the original electromechanical slot machines had tilt switches that would make or break a circuit to signal a fault.