[chowells]

> (which I gather has been corrected)

Indeed. In two different directions, even. First, a server can send a certificate with a large number of domain names in a field called "Subject Alternate Name" (SAN). If a server host a small number of static names, that's an easy solution.

Second, the client can use a TLS extension called "Server Name Indication" (SNI) to tell the server what name it's attempting to connect to. This is more recent than the SAN approach, and allows a single host to work for truly ridiculous sets of different names, even changing them dynamically.