In telecommunication, the term feed has the following meanings:
1. To supply a signal to the input of a system, subsystem, equipment, or component, such as a transmission line or antenna.
2. A coupling device between an antenna and its transmission line.
Note: A feed may consist of a distribution network or a primary radiator.
3. A transmission facility between (a) the point of origin of a signal, such as is generated in a radio or television studio, and (b) the head-end of a distribution facility, such as a broadcasting station in a network.
4. Pertaining to the function of inserting one thing into another, such as in a feed horn, paper feed, card feed, and line feed.
Source: from Federal Standard 1037C and from MIL-STD-188