thorax

thorax (noun; plural thoraxes, thoraces; Greek thorax, chest): 1. (Arthropoda: Chelicerata) In Arachnida, fused with the head to form the cephalothorax of spiders.

2. (Arthropoda: Crustacea) The tagma between the cephalon and abdomen comprising the anterior part of the trunk; cormus; pereon.

3. (Arthropoda: Insecta) a. The body region behind the head, bearing the legs and wings and encompassing the pro-, meso- and metathorax. b. In Hymenoptera, the second tagma of the body consisting of pro-, meso-, metathorax and the epinotum of Formicidae.