<p><strong>noun</strong></p><ul><li>the bone of the lower jaw.</li><li>(in birds) the lower part of the bill.</li><li>mandibles, the upper and lower parts of the bill.</li><li>(in arthropods) one of the first pair of mouthpart appendages, typically a jawlike biting organ, but styliform or setiform in piercing and sucking species.</li></ul>