is .eth a true TLD and belongs to DNS (Domain Name System)?

Question

I am reading blog posts about auctions of Etereum domian names under .eth suffix (going sky high in bidding), and I wonder, is .eth a really supported TLD ?

Because nslookup fails to resolve an ".eth" TLD:

[niko@localhost ~]$ nslookup -q=NS com
Server:     192.168.1.1
Address:    192.168.1.1#53

Non-authoritative answer:
com nameserver = d.gtld-servers.net.
com nameserver = k.gtld-servers.net.
com nameserver = c.gtld-servers.net.
com nameserver = l.gtld-servers.net.
com nameserver = g.gtld-servers.net.
com nameserver = f.gtld-servers.net.
com nameserver = j.gtld-servers.net.
com nameserver = a.gtld-servers.net.
com nameserver = m.gtld-servers.net.
com nameserver = b.gtld-servers.net.
com nameserver = e.gtld-servers.net.
com nameserver = h.gtld-servers.net.
com nameserver = i.gtld-servers.net.

Authoritative answers can be found from:

[niko@localhost ~]$ nslookup -q=NS eth
Server:     192.168.1.1
Address:    192.168.1.1#53

** server can't find eth: NXDOMAIN

[niko@localhost ~]$ 

Answer 1

It is not an official TLD.

The ICANN list of Top Level Domains is available from here. As you will see, .eth is not on it.

There are a number of unofficial TLDs that are set up by individual companies, and made available for money.

After all, StackOverflow itself can tell you how to do it...
What stops anyone from making their own top-level domain?

The .eth TLD is one of these. Set up by ENS. It is quite possible that .eth will become an official TLD in time, this has happened with similar unofficial TLDs in the past, e.g. .church.