ETYM back , n . + bone.
1. The bone running down the back of vertebrate animal; the spine.
2. A computer network that connects other computer networks.
3. (Informal) Fortitude; SYN. grit, guts, sand, gumption.
1. A network of communication transmission that carries major traffic between smaller networks. The backbones of the Internet, including communications carriers such as Sprint and MCI, can span thousands of miles using microwave relays and dedicated lines. 2. The smaller networks (compared with the entire Internet) that perform the bulk of the packet switching of Internet communication. Today these smaller networks still consist of the networks that were originally developed to make up the Internet—the computer networks of the educational and research institutions of the United States—especially NSFnet, the computer network of the National Science Foundation in Oak Ridge, Tennessee. See also NSFnet, packet switching. 3. The wires that carry major communications traffic within a network. In a local area network, a backbone may be a bus. Also called: collapsed backbone.
A high-speed line or series of connections that forms a major pathway within a network. The term is relative as a backbone in a small network will likely be much smaller than many non-backbone lines in a large network.