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

Results foryoko-mc.y.ecl.ntt.co.jp

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2016-10-03T04:00:49.304	2010-09-06T00:00:00	2011-09-17T23:59:59	yoko-mc.y.ecl.ntt.co.jp	yoko-mc.y.ecl.ntt.co.jp	C=US, O="VeriSign, Inc.", OU=VeriSign Trust Network, OU=Terms of use at https://www.verisign.com/rpa (c)09, CN=VeriSign Class 3 Secure Server 1024-bit CA - G2
2016-10-02T02:52:03.256	2012-08-28T00:00:00	2013-09-17T23:59:59	yoko-mc.y.ecl.ntt.co.jp	yoko-mc.y.ecl.ntt.co.jp	C=US, O="VeriSign, Inc.", OU=VeriSign Trust Network, OU=Terms of use at https://www.verisign.com/rpa (c)10, CN=VeriSign Class 3 Secure Server CA - G3
2016-10-01T20:56:31.227	2011-08-29T00:00:00	2012-09-16T23:59:59	yoko-mc.y.ecl.ntt.co.jp	yoko-mc.y.ecl.ntt.co.jp	C=US, O="VeriSign, Inc.", OU=VeriSign Trust Network, OU=Terms of use at https://www.verisign.com/rpa (c)10, CN=VeriSign Class 3 Secure Server CA - G3