Jiang Hu/Giang Hu/Gong Woo:
The proverbial setting of nearly all Chinese wuxia tales; it can be interpretted as any unsettled regions of medieval China without governance and where the common law has little to no jurisdiction. Jiang-Hu literally translates to "river-lake." Nearly every wuxia flick (Crouching Tiger, Hidden Dragon, Hero, House of Flying Daggers, etc.) in chinese makes reference to "Jiang Hu" in its dialog, usually in a metaphorical reference to the lot/state/lifestyle of being an outlaw warrior.
Modern use of the term has been adopted by many Chinese triad members to refer to the underworld or the society of triads. The term carries a connotation of conflict and lawlessness and is often evocative of a sense of honor or chilvary, and unspoken rules amongst fighters.
EDIT: Glowing Fish notes that the term's literal meaning is most-likely rooted in the 14th century novel, The Water Margin, which contains tales about different instances of heroic acts committed by virtuous men who were outcasts of their society.