look up any word, like smh:
 
1.
One who acts in various states of dorkiness throughout the day. A typical Wallgren hangs out with Asians in the hope of absorbing some intelligence, but instead usually gets justifiably picked on.
Dude, you're such a Wallgren. (said to a blond loser getting beat up by an Asian gang).
by A.S. January 31, 2004
 
2.
The annoying habit of having to visit the restroom before going out. Results in tardy lunch dates and annoyed companions. Generally a wallgren is pulled, as in "pull a wallgren".
Pat: Dude, wait up. I have to pull a wallgren.

Jim: Damn it. We're gonna be late for batting practice.
by WS February 03, 2004