The human body has numerous parts, and some of them have names that are quite difficult to remember. One such term is "thoraces," which refers to the plural of thorax. The thorax is the part of the body between the neck and the abdomen that encases the lungs and heart, among other organs. When it comes to antonyms for thoraces, there isn't really a direct opposite, as it is a noun that refers to a specific anatomical structure. However, some words that could be associated with the opposite of thoraces might include "limbs," "brain," and "abdomen.