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

Results forwww.averel.grnet-hq.admin.grnet.gr

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2018-09-11T23:14:50.041	2018-09-03T00:00:00	2020-09-23T12:00:00	averel.grnet-hq.admin.grnet.gr	averel.grnet-hq.admin.grnet.gr	C=NL, ST=Noord-Holland, L=Amsterdam, O=TERENA, CN=TERENA SSL CA 3
2018-09-03T08:03:42.339	2018-09-03T00:00:00	2020-09-23T12:00:00	averel.grnet-hq.admin.grnet.gr	averel.grnet-hq.admin.grnet.gr	C=NL, ST=Noord-Holland, L=Amsterdam, O=TERENA, CN=TERENA SSL CA 3
2018-09-03T07:50:22.118	2018-09-03T00:00:00	2020-09-23T12:00:00	averel.grnet-hq.admin.grnet.gr	averel.grnet-hq.admin.grnet.gr	C=NL, ST=Noord-Holland, L=Amsterdam, O=TERENA, CN=TERENA SSL CA 3
2018-03-30T01:36:04.611	2012-09-18T00:00:00	2015-09-18T23:59:59	averel.grnet-hq.admin.grnet.gr	averel.grnet-hq.admin.grnet.gr	C=NL, O=TERENA, CN=TERENA SSL CA
2018-01-19T05:03:06.619	2015-09-07T00:00:00	2018-09-11T12:00:00	averel.grnet-hq.admin.grnet.gr	averel.grnet-hq.admin.grnet.gr	C=NL, ST=Noord-Holland, L=Amsterdam, O=TERENA, CN=TERENA SSL CA 3