look up any word, like dirty sanchez:
 
1.
In the game Counter Strike Source, a counter terrorist is skum (worthless garbage that needs to be humiliated and sliced into little pieces with a knife).
Lets humiliate the CT skum!!! HUMILIATION!!!
by STUNTMAN [1337 CT HUMILIATOR] April 09, 2008
 
2.
Of or relating to the group of bmx'ers characterized by greasy hair, shitty attitudes, often missing front two teeth, in times poor education and grammar, and are more commonly found residing in Arizona. Can also refer to something as being "skummy."
also:
skum of the earth
skum love
pond skum
skum cave/lair
"Dude Gary, your skum."
by sixtyfifen February 19, 2008