Backbone

[Sonia]

The column of bones in the back which sustains and gives
firmness to the frame; the spine; the vertebral or spinal column.

[Julene]

Just like the human backbone carries signals to many smaller nerves in the body, a network backbone carries data to smaller lines of transmission. A local backbone refers to the main network lines that connect several local area networks (LANs) together. The result is a wide area network (WAN) linked by a backbone connection.
The Internet, which is the ultimate wide area network, relies on a backbone to carry data over long distances. The Internet backbone consists of several ultra-high bandwidth connections that link together many different nodes around the world. These nodes route incoming data to smaller networks in the local region. The fewer hops your data needs to make before reaching the backbone, the faster it will get sent to the destination. This is why many Web hosts and ISPs have direct connections to the Internet backbone.

[Julian]

The series of vertebrae extending from the skull to the pelvis; the spine.

[Couch Potatoe]

Product development platform for direct to consumer economy A software product by PurchasingNet

[Dorothey Allen]

the line of bones down the centre of the back that provides support for the body: