In communications, a feeder line is a peripheral route or branch from a main line or trunk line.
A transmission line is sometimes called a feeder. In radio engineering, a feeder is a line connecting radio equipment to an antenna, usually open wire (air-insulated wire line) or twin-lead from a shortwave transmitter. In power engineering, a feeder line is part of an electric distribution network, usually a radial circuit of intermediate voltage.
While applicable to any area of communication making using of a hierarchical network, the term is particularly used in US air travel and rail transport.
Efficient, high-capacity routes connect important nodes while feeder lines connect these nodes to departure and destination points.