The sternum, also known as the breastbone, is a flat bone at the front of the chest. It is an essential part of the human body as it connects the ribs and protects vital organs such as the heart and lungs. There are several synonyms for the word sternum, including the thorax, the chest bone, and the thoracic cage. Other terms used to describe this important bone are the manubrium, gladiolus, and xiphoid process. These synonyms help us to understand the anatomy of the human body and how the sternum functions in protecting our internal organs.