The Wailing Caverns or wc is an instance in World of Warcraft for approximately levels 15-21. An extraordinarily long and overly complicated dungeon, with poor groups (pugs) it can take a horrifyingly long time, though the rewards (xp and items from quests, plus loot and xp from killing mobs) sometimes make it worth it.

Usually, however, it takes way longer than expected, making your ass fall asleep and become numb. Can be used whenever something forces you to stay at the computer far longer than expected.
Burned-out raider: Oh god, this naxx25 started out so well, then we wiped on 4horsemen for so long I got some major Wailing Caverns Ass.
by impsythealmighty May 12, 2009
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