A slot is a narrow opening into which something can fit, as a keyway in a lock or a slit for a coin in a machine. It may also refer to a position in a list or schedule, especially one that is reserved for a particular activity. The phrase is also used to describe an allocated time or space for an aircraft to take off or land, as authorized by air traffic control:

A penny slot is a casino game that offers small payouts on each spin of the reels. These machines are designed to be extra appealing, with bright lights and jingling jangling sounds that attract players like bees to honey. But a player must protect his or her bankroll by playing responsibly and following certain rules.

There are many different slot games available in casinos, from the classic three-reel versions to the more advanced multi-line video slots with high payouts and bonus features. Most slot games have a theme, and the symbols and other bonus features are aligned with that theme. Some even offer progressive jackpots that can reach into the millions of dollars.

The term “slot” is also used to refer to a position on the football field, particularly for the quick and agile wide receiver who lines up in between the offensive tackle and the tight end. The slot receiver is often used on running plays, where he or she can block for the ball carrier and help set up sweeps and slant runs. On passing plays, the slot receiver can run routes that correspond with other receivers on the team in order to confuse the defense.

Traditionally, slot machines used revolving mechanical reels to display and determine winning combinations. They can be operated by inserting cash, paper tickets with a barcode, or, in “ticket-in, ticket-out” machines, a magnetic stripe card. The reels then spin and stop to rearrange the symbols, with the player earning credits based on a paytable. Modern slot machines have electronic reels that are controlled by a microprocessor.

A slot is also the name of an allocated, scheduled time and place for an aircraft to take off or land, typically as authorized by an airport or air-traffic authority: The new airline was awarded 40 more slots at U.S. airports. See under slat1 (def. 2). In ornithology, it is a narrow notch between the tips of the primaries of certain birds that during flight helps to maintain a smooth flow of air over the wings.