The name localhost is reserved by the Internet Engineering Task Force (IETF) as a domain name label that may not be installed as a top-level domain in the Domain Name System (DNS) of the Internet.
via Wikipedia infobox
The name localhost is reserved by the Internet Engineering Task Force (IETF) as a domain name label that may not be installed as a top-level domain in the Domain Name System (DNS) of the Internet.
==Reserved DNS names== In 1999, the Internet Engineering Task Force reserved the DNS labels , , , and so that they may not be installed into the root zone of the Domain Name System.
Discovered by embedding cosine similarity (sentence-transformers MiniLM, 384-dim).