iouglossary / IOU IOU (I-oh-yoo). [abbr. “I owe you”]1. A memorandum acknowledging a debt.2. The debt itself. — Also termed due-bill. 词条贡献者 译者Susanne,世界顶尖法学院国际税法专业,擅长翻译各种与联邦税务纠纷相关的法律文件。