Definition of thorax
noun (plural thoraxes or thoraces /ˈTHôrəˌsēz/) Anatomy & Zoology
the part of the body of a mammal between the neck and the abdomen, including the cavity enclosed by the ribs, breastbone, and dorsal vertebrae, and containing the chief organs of circulation and respiration; the chest. Zoology the corresponding part of a bird, reptile, amphibian, or fish. Entomology the middle section of the body of an insect, between the head and the abdomen, bearing the legs and wings.