1. A disappointed expression with a pouty mouth and squinty eyes. 2. Shows a person that disagrees with you or doesn't want to talk further about something; can show lack of care or that the person thinks something is lame. 3. A more extreme way of saying "whatever" i.e. "fuck this shit, man whatevz"
Dude, I'm not mean, I'm never mean to anyone. You know what, Rodryface. -_-