"vhost" stands for "vanity host". It's a domain name you can use when you're connected to a server that offers them for use in IRC. That'll usually be a shell account providers server. Instead of connecting as "omg@AOL.com" you can be "omg@this.stuff.suxxx.doesnt.it". If you think this allows you to muck around and do bad sh*t, think again.
If you Google for "vhost BNC" or "shell account eggdrop" or "vhost irc spoof" or "psyBNC" you'll find lotsa
info. Also note IRC clients and anything related are famous for containing backdoors and other "fun" and will lower your systems security posture. Make sure you verify sources before compiling.
