Wiktionary
alt. (context Internet English) A program or server that maps human-readable names to computer addresses, especially as part of the Domain Name System. n. (context Internet English) A program or server that maps human-readable names to computer addresses, especially as part of the Domain Name System.
Wikipedia
A name server is a computer hardware or software server that implements a network service for providing responses to queries against a directory service. It translates an often humanly-meaningful, text-based identifier to a system-internal, often numeric identification or addressing component. This service is performed by the server in response to a service protocol request.
An example of a name server is the server component of the Domain Name System (DNS), one of the two principal namespaces of the Internet. The most important function of DNS servers is the translation (resolution) of human-memorable domain names and hostnames into the corresponding numeric Internet Protocol (IP) addresses, the second principal name space of the Internet which is used to identify and locate computer systems and resources on the Internet.
Usage examples of "name server".
We're going to do some port surfing on this last AOL domain name server!