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

Results forroot.macosforge.org

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2016-09-20T18:18:29.36	2010-04-02T20:49:08	2011-05-02T21:19:05	*.macosforge.org	*.macosforge.org	C=US, O="Entrust, Inc.", OU=www.entrust.net/rpa is incorporated by reference, OU="(c) 2009 Entrust, Inc.", CN=Entrust Certification Authority - L1C
2014-05-22T13:27:46.968	2014-05-05T22:29:57	2016-05-06T02:15:58	*.macosforge.org	*.macosforge.org	C=US, O="Entrust, Inc.", OU=www.entrust.net/rpa is incorporated by reference, OU="(c) 2009 Entrust, Inc.", CN=Entrust Certification Authority - L1C
2013-03-26T11:17:00.51	2011-04-28T21:45:15	2014-05-31T09:51:08	*.macosforge.org	*.macosforge.org	C=US, O="Entrust, Inc.", OU=www.entrust.net/rpa is incorporated by reference, OU="(c) 2009 Entrust, Inc.", CN=Entrust Certification Authority - L1C