Dictionary.net

• A United States government bond, issued during the World War, as security for repayment of money lent to the government for war expenses.

1919 - The Winston Simplified Dictionary
By William Dodge Lewis, Edgar Arthur Singer

• A war interest-bearing debt certificate, issued by the United States Government. 1917-19.

1919 - The Concise Standard Dictionary of the English Language
By James Champlin Fernald