(CNAME) A host's official name as opposed to an alias. The official name is the first hostname listed for its Internet address in the hostname database, /etc/hosts or the Network Information Service (NIS) map hosts.byaddr ("hosts" for short). A host with multiple network interfaces may have more than one Internet address, each with its own canonical name (and zero or more aliases).
You can find a host's canonical name using nslookup if you say
set querytype=CNAMEand then type a hostname.
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Nearby terms: candygrammar « canonical « Canonical Encoding Rules « canonical name » canonicity » C (ANSI) » can't happen