A registration for an early network dictionary service that no longer exists in the wild.
IANA lists 765 as "webster", registered by Josyula R. Rao, for a network dictionary-lookup service from the pre-web era. No RFC was published for it, and the role it filled was later taken by DICT (RFC 2229), which is a different protocol on port 2628. There is no maintained webster server today. An open 765 is almost certainly an unrelated locally configured service.
Expose with care
The registered service is extinct, so anything answering here is unidentified until you fingerprint it.
$ nmap -sV -p 765 TARGETSeen this on your network? Beige Box scans your Wi-Fi and shows every open port on every device — and its Ports tool links straight back here.
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