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

Results for*.test.local.sombrainc.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2020-07-11T17:01:16.876	2020-07-11T16:01:16	2020-10-09T16:01:16	*.test.local.sombrainc.com	*.test.local.sombrainc.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-07-11T17:01:16.876	2020-07-11T16:01:16	2020-10-09T16:01:16	*.test.local.sombrainc.com	*.test.local.sombrainc.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-07-11T17:01:16.619	2020-07-11T16:01:16	2020-10-09T16:01:16	*.test.local.sombrainc.com	*.test.local.sombrainc.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-07-11T17:01:16.619	2020-07-11T16:01:16	2020-10-09T16:01:16	*.test.local.sombrainc.com	*.test.local.sombrainc.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3