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

Results for*.staging.officehost.cloud

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2020-04-24T09:54:34.922	2020-04-24T08:54:34	2020-07-23T08:54:34	*.staging.officehost.cloud	*.staging.officehost.cloud	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-04-24T09:54:34.922	2020-04-24T08:54:34	2020-07-23T08:54:34	*.staging.officehost.cloud	*.staging.officehost.cloud	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-04-24T09:54:34.782	2020-04-24T08:54:34	2020-07-23T08:54:34	*.staging.officehost.cloud	*.staging.officehost.cloud	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2020-04-24T09:54:34.782	2020-04-24T08:54:34	2020-07-23T08:54:34	*.staging.officehost.cloud	*.staging.officehost.cloud	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3