Used attributively in five-twenty bonds (or shortly five-twenties), certain bonds issued by the U.S. government in 1862, 1864, and 1865; so called from being redeemable at any time after five years from date of issue and payable in full at the end of twenty years.
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1879 Webster's Amer. Dict. Eng. Lang. Suppl. 1557/1Five-twenty, noting a bond issued by the government of the United States.