1. noun
a) A container for liquids or gases, typically with a volume of several cubic metres.
2. verb
a) To fail or fall (often used in describing the economy or the stock market); to degenerate or decline rapidly; to plummet.
Beforehand, Swedish [national ice hockey team] coach Bengt-Ake Gustafsson had ruminated about tanking against Slovakia to avoid powerful Canada or the Czechs in the quarters [i.e., quarterfinals of the 2006 Winter Olympic tournament], telling Swedish television, "One is cholera, the other the plague."
b) (Video game jargon) To attract the attacks of an enemy target in cooperative team-based combat, so that ones teammates can defeat the enemy in question more efficiently.
Wikipedia foundation.