time slot

period of time set aside for broadcasting a program or advertisement in the program schedule of television or radio stations

This article is about the medium access technology. The name "TDMA" is also commonly used in the United States to refer to a specific second generation (2G) mobile phone standard, more properly referred to as IS-136 or D-AMPS Time division multiple access (TDMA) is a channel access method for shared medium (usually radio) networks. It allows several users to share the same frequency channel by dividing the signal into different timeslots. The users transmit in rapid succession, one after the other, each using his own timeslot. This allows multiple stations to share the same transmission medium (e.g. radio frequency channel) while using only the part of its bandwidth they require. TDMA is used in the digital 2G cellular systems such as Global System for Mobile Communications (GSM), IS-136, Personal Digital Cellular (PDC) and iDEN, and in the Digital Enhanced Cordless Telecommunications (DECT) standard for portable phones. It is also used extensively in satellite systems, and combat-net radio systems. For usage of Dynamic TDMA packet mode communication, see below.
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Noun
1. a time assigned on a schedule or agenda; "the TV program has a new time slot"; "an aircraft landing slot"
(synonym) slot
(hypernym) time interval, interval

1. Period of time during which certain activities are governed by specific regulations. [JP1] 2. A time interval that can be recognized and uniquely defined. (188 )

specific time bought for airing a commercial on radio or television.