thorax

n. area between the neck and abdomen, chest (of four-legged animals); middle body segment of an insect crustacean or arachnid

This article mainly refers to animal anatomy. See Chest for the human anatomy article.The thorax is a division of an animal's body that lies between the head and the abdomen.In mammals, the thorax is the region of the body formed by the sternum, the thoracic vertebrae and the ribs. It extends from the neck to the diaphragm, not including the upper limbs. The heart and the lungs reside in the thoracic cavity, as well as many blood vessels. The inner organs are protected by the rib cage and the sternum.
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Thorax /tho·rax/ pl. tho´races [Gr.] chest ; the part of the body between the neck and diaphragm, encased by the ribs. [more]Thorax - Community and Resources

Noun
1. the middle region of the body of an arthropod between the head and the abdomen
(hypernym) body part
(part-holonym) arthropod
2. the part of the human body between the neck and the diaphragm or the corresponding part in other vertebrates
(synonym) chest, pectus
(hypernym) body part
(hyponym) female chest
(part-holonym) torso, trunk, body
(part-meronym) sternum, breastbone
3. part of an insect's body that bears the wings and legs
(hypernym) body part
(hyponym) prothorax
(part-holonym) insect

n. thorax, area between the neck and abdomen, chest (of four-legged animals); middle body segment of an insect crustacean or arachnid