from
The Free On-line Dictionary of Computing (8 July 2008)
network segment
<networking> A part of an {Ethernet} or other network, on
which all message traffic is common to all nodes, i.e. it is
broadcast from one node on the segment and received by all
others. This is normally because the segment is a single
continuous conductor, though it may include {repeaters}(?).
Since all nodes share the physical medium, {collision
detection} or some other {protocol} is required to determine
whether a message was transmitted without interference from
other nodes. The receiving node inspects the destination
address of a {packet} to tell if it was (one of) the intended
recipient(s).
Communication between nodes on different segments is via one
or more {routers}.
(1996-10-16)