<p><strong>Noun</strong></p><ul><li>a warrant, pledge, or formal assurance given as security that another's debt or obligation will be fulfilled.</li><li>something that is taken or presented as security.</li><li>the act of giving security.</li><li>a person who acts as a guarantor.</li></ul><p><strong>Verb</strong></p><ul><li>to guarantee.</li></ul>