<p><strong>Adjective</strong></p><ul><li>occurring or existing simultaneously or side by side: concurrent attacks by land, sea, and air.</li><li>acting in conjunction; cooperating: the concurrent efforts of several legislators to pass the new law.</li><li>having equal authority or jurisdiction: two concurrent courts of law.</li><li>accordant or agreeing: concurrent testimony by three witnesses.</li><li>tending to or intersecting at the same point: four concurrent lines.</li></ul><p><strong>Noun</strong></p><ul><li>something joint or contributory.</li><li>Archaic: a rival or competitor.</li></ul>