Assign 2nd domain to nominated folder in root

Hi Guys,

Totally new to Linode. I have a domain set up say xyz.com in the publichtml folder which all works fine. How do I set up a second domain say abc.com so that when the user navigates to my site (abc.com) the files in say publichtml/abc_com/ folder are displayed?

As it stands both domains show the files in public_html root. Is it done thru CNAME or something else?

Thanks