Fully Qualified Domain Name

A fully qualified domain name (FQDN) is a domain name that specifies the exact location of a host within the tree hierarchy of the Domain Name System (DNS). A FQDN is a domain name that includes a host name, a root domain and a top level domain. It may also include additional subdomains between the root domain and the host name. An incomplete FQDN is referred to a a partially qualified domain name.