What does IOU stand for?

What does IOU mean?

IOU	Investor Owned Utilities Internet » Chat
IOU	I Owe You Business » General
IOU	I Owe Unto Internet » Chat
IOU	Ile Ouen, New Caledonia Regional » Airport Codes
IOU	Is Owed Unto .... Business » Accounting
IOU	Iron And Oreminers United Miscellaneous » Unclassified
IOU	Intensive Therapy Observation Unit. Medical » Laboratory
IOU	Intensive therapy Observation Unit Medical » Physiology
IOU	International Octel Users Computing » General
IOU	Innovative Original Unique Miscellaneous » Unclassified
IOU	Inform Open Unite Miscellaneous » Unclassified
IOU	Input/Output Unit Governmental » NASA
IOU	Internal Office Use Business » General

IOU(n.): a written acknowledgment of a debt, esp. an informal one consisting only of the letters IOU, the sum owed, and the debtor's signature.