The term "delts" is an abbreviation for the deltoid muscles, which are the muscles that form the rounded shape of our shoulders. These muscles are crucial for performing activities such as lifting, pushing, and pulling. There are several synonyms that are commonly used to refer to these muscles, including deltoids, shoulder muscles, and delt muscles. Other more colloquial synonyms for the delts include "cannonball shoulders", "shoulder caps", and "boulder shoulders". These synonyms are often used in fitness communities when discussing workouts or training programs that focus on developing these muscles. Regardless of the terminology used, the delts are an essential muscle group for anyone looking to build strong, functional upper body strength.