A slit or narrow opening, usually used to receive something such as a coin or letter. Also: a position in a series or sequence, or an appointment with a healthcare professional.
In gambling, a slot is one of the positions on a pay line on a machine that has matching symbols to win. Each machine has a specific pay table that lists the number of credits a player will get if the symbols match on a winning line. This information is usually displayed above and below the reels, or within a help menu on video slots.
Historically, many slot machines were operated in saloons or dance halls and required coins for play. However, the popularity of these machines led to laws limiting their sale and use in public places. Many of these laws were based on the belief that slot machines were a source of organized crime. In fact, most of the crimes committed with slot machines were not associated with organized crime at all.
In aviation, a “slot” is an authorization to take off or land at a specific airport during a given time period. This is an important tool used in highly congested airspace to reduce the amount of fuel that must be burned by aircraft waiting for a clear runway, as well as to prevent repeated delays caused by too many planes trying to take off and land at the same time. The use of slot management is expanding worldwide to address airport congestion and improve safety, efficiency and environmental performance.