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

Results for*.triple7.dev

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2019-03-23T23:36:16.371	2019-03-21T00:00:00	2020-03-21T12:00:00	sni.cloudflaressl.com	*.triple7.dev	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2
2019-03-23T23:36:16.371	2019-03-21T00:00:00	2020-03-21T12:00:00	sni.cloudflaressl.com	*.triple7.dev	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2
2019-03-21T21:25:19.259	2019-03-21T00:00:00	2020-03-21T12:00:00	sni.cloudflaressl.com	*.triple7.dev	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2
2019-03-21T21:25:19.259	2019-03-21T00:00:00	2020-03-21T12:00:00	sni.cloudflaressl.com	*.triple7.dev	C=US, ST=CA, L=San Francisco, O="CloudFlare, Inc.", CN=CloudFlare Inc ECC CA-2