Redirect or mask URL to external wordpress URL

I have a blog at http://www.abc.com/wordpress.

I have another site http://www.xyz.com that I want to completely redirect to my wordpress content but still have the URL name xyz.com. Is that possible? Problem is the hosting company for xyz.com wants to charge me something outrageous to support MYSQL db.

Also, I want search engines to recognize the abc.com wordpress content as part of xyz.com.

I’ve bee studying 301, index.php, and htaccess, but don’t really feel like I’ve found the right answer yet.

Thanks!