In mammals, the parts that make up the thorax are the sternum, the thoracic vertebrae and the ribs. It starts from the neck and stops at the diaphragm. Women develop breasts on the chest during puberty, while male chests generally remain flat, while gaining muscle and many men grow chest hair. chest noun [C] (BOX) a large, strong box, usually made of wood, which is used for storing valuable goods or possessions or for moving possessions from one place to another Read the latest articles of CHEST at ScienceDirect.com, Elsevier’s leading platform of peer-reviewed scholarly literature The American College of Chest Physicians (CHEST) is the global leader in advancing best patient outcomes through innovative chest medicine education, clinical research, and team-based care. Humans have 25 bones in the chest that together protects several vital organs and provide shape and structure to the upper body. These bones collectively form the thorax, one of the most critical structures in the human body. Our mission is to champion the prevention, diagnosis, and treatment of chest diseases through education, communication, and research. More on CHEST Opens in new window. The meaning of CHEST is a container for storage or shipping; especially : a box with a lid used especially for the safekeeping of belongings. How to use chest in a sentence. Define chest. chest synonyms, chest pronunciation, chest translation, English dictionary definition of chest. n. 1. a. The part of the body between the neck and the abdomen, enclosed by the ribs and the breastbone; the thorax. b. The front or ventral portion of this. Your chest is the upper part of the trunk of your body, stretching from your neck to your abdomen. It holds and protects some of your most important organs. In humans and other hominids, the thorax is the chest region of the body between the neck and the abdomen, along with its internal organs and other contents. It is mostly protected and supported by the rib cage, spine, and shoulder girdle.