<p><strong>Adjective:</strong></p><ul><li>of, relating to, or causing death; deadly; fatal: a lethal dose.</li><li>a lethal weapon; a lethal dose.</li><li>made or carried out to cause death: a lethal attack.</li><li>a lethal chamber; a lethal attack.</li><li>causing great harm or destruction: The disclosures were lethal to his candidacy.</li></ul>