THORACOSTRACA
Tho`ra*cos"tra*ca, n. pl. Etym: [NL. See Thorax, and Ostracoid, a.]
(Zoöl.)
Defn: An extensive division of Crustacea, having a dorsal shield or carapec
THORACOTOMY
Tho`ra*cot"o*my, n. Etym: [Gr. (Surg.)
Defn: The operation of opening the pleural cavity by incision.
THORAL
Tho"ral, a. Etym: [L. torus a couch, bed.]
Defn: Of or pertaining to a bed. [R.]
THORAX
Tho"rax, n. Etym: [L., fr. Gr.
1. (Anat.)
Defn: The part of the trunk between the neck and the abdomen, containing that part of the body cavity the walls of which are supported by the dorsal vertebræ, the ribs, and the sternum, and which the heart and lungs are situated; the chest.
Note: In mammals the thoracic cavity is completely separated from the abdominal by the diaphragm, but in birds and many reptiles the separation is incomplete, while in other reptiles, and in amphibians and fishes, there is no marked separation and no true thorax.