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

Results forwww.dev-project.cloudandthing.com

Logged At	Not Before	Not After	Common Name	Matching Identities	Issuer Name
2018-07-24T12:45:56.784	2018-07-24T11:45:56	2018-10-22T11:45:56	dev-project.cloudandthing.com	dev-project.cloudandthing.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2018-07-24T12:45:56.147	2018-07-24T11:45:56	2018-10-22T11:45:56	dev-project.cloudandthing.com	dev-project.cloudandthing.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2018-05-25T03:00:42.61	2018-05-25T02:00:42	2018-08-23T02:00:42	dev-project.cloudandthing.com	dev-project.cloudandthing.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3
2018-05-25T03:00:42.481	2018-05-25T02:00:42	2018-08-23T02:00:42	dev-project.cloudandthing.com	dev-project.cloudandthing.com	C=US, O=Let's Encrypt, CN=Let's Encrypt Authority X3