man·di·ble / ˈmandəbəl/ • n. Anat. & Zool. the jaw or a jawbone, esp. the lower jawbone in mammals and fishes. ∎  either of the upper and lower parts of a bird's beak. ∎  either half of the crushing organ in an arthropod's mouthparts.DERIVATIVES: man·dib·u·lar / manˈdibyələr/ adj.man·dib·u·late / manˈdibyəˌlāt/ adj.

mandible
1. One of a pair of horny mouthparts in insects, crustaceans, centipedes, and millipedes. The mandibles lie in front of the weaker maxillae and their lateral movements assist in biting and crushing the food.

2. The lower jaw of vertebrates.

3. Either of the two parts of a bird's beak.

mandible In Crustacea, Insecta, and Myriapoda (centipedes, millipedes, etc.), one of the pair of mouth-parts most commonly used for seizing and cutting food. In birds, specifically the lower jaw but the term is also used to denote the two parts of the bill of a bird, as upper and lower mandibles.

mandible
1. In vertebrates, the lower jaw.

2. In birds, specifically the lower jaw and bill but the term is also used to denote the two parts of the bill of a bird, as upper and lower mandibles.

3. In Arthropoda, one of the pair of mouth-parts most commonly used for seizing and cutting food.

mandible (man-dib-ŭl) n. the lower jawbone. It consists of a horseshoe-shaped body, the upper surface of which bears the lower teeth, and two vertical parts (rami). See also temporomandibular joint.
—mandibular (man-dib-yoo-ler) adj.