Used by the gaming community known as the Acolytes. It is used to express something positive that has happened to the community or someone in it.
by Hiezu January 28, 2010
An exclimation of excitement or joy.
by Theo Rosenthal January 24, 2007
by Daniel "El Hefe" Posner September 03, 2003
After Brigadier General Thomas R. R. Cobb's Irish Regiment of Georgia pushed back Lieutenant Colonel St. Clair Mullholands Irish Brigade, a Captain (3 stripes on the collar) took off his hat and started yelling "Haroo! Haroo!" and the rest of the regiment cheered "Haroo!"
by Jedi_Master June 16, 2008