When something really lame occurs, one may exclaim "D.U."

lil mad is like big mad but the opposite, you mad but not mad to the extent of pullin somthin

DU(Drunks united) was started on October 15, 2006 by Thomas G from Smithtown High School. Immediately members flocked to DU marking the start of DU as we know it today. Later, three unusually slutty women(ranging from 130-450 lbs), joined followed by a junior at the time. Two months later these ladies were dropped from the group. DU has a total penis length of 250 feet, and is ethnically 83% white and 17% nazi. A negligible percent are asian.

A contracted form of the word dude. In the same way foo is the shortened version of fool.

Do and you combined

Acronym - Dangerous Underpants Situation

Code for the Democratic Underground web site. Used on other web sites that don't want to be found by DU residents searching for people talking about the DU. Sometimes used as DUh.