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Medical Term:


Pronunciation: tho'raks, tho-ra'sis, -ra'sez


The upper part of the trunk between the neck and the abdomen; formed by the 12 thoracic vertebrae, the 12 pairs of ribs, the sternum, and the muscles and fasciae attached to these; below, it is separated from the abdomen by the diaphragm; it contains the chief organs of the circulatory and respiratory systems.

[L. fr. G. thorax, breastplate, the chest, fr. thoresso, to arm]

© Copyright 2017 Wolters Kluwer. All Rights Reserved. Review Date: Sep 19, 2016.