In Warcraft 2, this word is used by an Orcish grunt/peon. Just click on the Orc a few times and he'll say it. Swubu is the confirmation sound, dabu as well.
The sound when Link from the Zelda series swings his sword.
It's often in a line of yells which are screamed by Adult Link in The Ocarina of Time. See hid and sjaad as well