frontal part of the thorax
The chest is the front part of the torso. It is between the neck and abdomen.
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.
In insects and crustaceans, it is the middle of the three main body sections. The walking legs are usually on the thorax.