It can be anything! An apex, subdomain, or even a URL.

Results forwww.dns3.usethisnameserver.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2021-01-24T05:23:45.32	2021-01-24T00:00:00	2022-01-24T23:59:59	dns3.usethisnameserver.com	www.dns3.usethisnameserver.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2021-01-24T05:23:44.691	2021-01-24T00:00:00	2022-01-24T23:59:59	dns3.usethisnameserver.com	www.dns3.usethisnameserver.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2020-05-19T05:17:42.589	2020-05-19T00:00:00	2021-05-19T23:59:59	dns3.usethisnameserver.com	www.dns3.usethisnameserver.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2020-05-19T05:17:41.144	2020-05-19T00:00:00	2021-05-19T23:59:59	dns3.usethisnameserver.com	www.dns3.usethisnameserver.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"