[{"Bold_text": "adjective", "List Items": ["occurring or existing simultaneously or side by side:concurrent attacks by land, sea, and air.", "acting in conjunction; cooperating:the concurrent efforts of several legislators to pass the new law.", "having equal authority or jurisdiction:two concurrent courts of law.", "accordant or agreeing:concurrent testimony by three witnesses.", "tending to or intersecting at the same point:four concurrent lines."]}, {"Bold_text": "noun", "List Items": ["something joint or contributory.", "Archaic.a rival or competitor."]}]