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

Results for*.mirastic.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2018-10-07T23:04:35.124	2018-10-02T00:00:00	2019-10-02T12:00:00	sni.cloudflaressl.com	*.mirastic.com	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2
2018-10-07T23:04:35.124	2018-10-02T00:00:00	2019-10-02T12:00:00	sni.cloudflaressl.com	*.mirastic.com	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2
2018-10-02T16:00:23.068	2018-10-02T00:00:00	2019-10-02T12:00:00	sni.cloudflaressl.com	*.mirastic.com	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2
2018-10-02T16:00:23.068	2018-10-02T00:00:00	2019-10-02T12:00:00	sni.cloudflaressl.com	*.mirastic.com	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2