subnet

n. (Computers) separate division of a larger computer network; physical network of an internet (Internet); division of a computer network (in IP)

The word subnet may refer to:An abbreviation for subnetworkIn mathematics, a subnet of a net in a topological space.
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A portion of a network, which may be a physically independent network segment, which shares a network address with other portions of the network and is distinguished by a subnet number. A subnet is to a network what a network is to an internet.