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

Results forwebdisk.facetemp.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2021-02-28T23:13:08.86	2021-02-28T22:13:08	2021-05-29T22:13:08	facetemp.graftekimaging.com	webdisk.facetemp.com	C=US, O=Let's Encrypt, CN=R3
2021-02-28T23:13:08.659	2021-02-28T22:13:08	2021-05-29T22:13:08	facetemp.graftekimaging.com	webdisk.facetemp.com	C=US, O=Let's Encrypt, CN=R3
2020-12-29T23:08:51.77	2020-12-29T22:08:51	2021-03-29T22:08:51	mail.graftekimaging.com	webdisk.facetemp.com	C=US, O=Let's Encrypt, CN=R3
2020-12-29T23:08:51.48	2020-12-29T22:08:51	2021-03-29T22:08:51	mail.graftekimaging.com	webdisk.facetemp.com	C=US, O=Let's Encrypt, CN=R3
2020-10-29T22:07:38.214	2020-10-29T21:07:37	2021-01-27T21:07:37	webdisk.graftekimaging.com	webdisk.facetemp.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-10-29T22:07:37.945	2020-10-29T21:07:37	2021-01-27T21:07:37	webdisk.graftekimaging.com	webdisk.facetemp.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3