or I.O.U.


a written acknowledgment of a debt, especially an informal one consisting only of the letters IOU, the sum owed, and the debtor's signature.

Origin of IOU

First recorded in 1610–20; representing I owe you Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

Related Words for iou

chit, debenture, bill, debt

Examples from the Web for iou

Contemporary Examples of iou

  • She is the author of the bestsellers The Silent Takeover and IOU: The Debt Threat .

    The Daily Beast logo
    The New Co-op Capitalism

    Noreena Hertz

    February 23, 2009

Historical Examples of iou

British Dictionary definitions for iou



a written promise or reminder to pay a debt

Word Origin for IOU

C17: representing I owe you
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

iou in Culture


Abbreviation for “I owe you.” An IOU is a written statement of a borrower's obligation to pay a debt.

The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.