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

Results forwebmail.azeeno.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2018-04-24T18:19:25.986	2018-04-24T00:00:00	2018-07-23T23:59:59	azeeno.com	webmail.azeeno.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2018-04-24T18:19:01.557	2018-04-24T00:00:00	2018-07-23T23:59:59	azeeno.com	webmail.azeeno.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2018-02-10T18:26:13.002	2018-02-07T00:00:00	2018-05-08T23:59:59	azeeno.com	webmail.azeeno.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"
2017-11-26T18:06:00.035	2017-11-23T00:00:00	2018-02-21T23:59:59	azeeno.com	webmail.azeeno.com	C=US, ST=TX, L=Houston, O="cPanel, Inc.", CN="cPanel, Inc. Certification Authority"