<p><strong>Verb (used with object)</strong></p><ul><li>to assemble (troops, a ship's crew, etc.), as for battle, display, inspection, orders, or discharge.</li><li>to gather, summon, rouse (often followed by up): He mustered all his courage.</li></ul><p><strong>Verb (used without object)</strong></p><ul><li>to assemble for inspection, service, etc., as troops or forces.</li><li>to come together; collect; assemble; gather.</li></ul><p><strong>Noun</strong></p><ul><li>an assembling of troops or persons for formal inspection or other purposes.</li><li>an assemblage or collection.</li><li>the act of mustering.</li><li>also called muster roll: a list of the persons enrolled in a military or naval unit.</li></ul><p><strong>Verb Phrase</strong></p><ul><li>to discharge from service in the armed forces: He will be mustered out of the army in only two more months.</li><li>to enlist into service in the armed forces.</li></ul>