The United States Marine Corps, also known as USMC, is one of the most respected military branches in the world. When referring to this branch of service, there are several synonyms that can be used to describe USMC. Some of these synonyms include the Marines, the Corps, Leathernecks, Devil Dogs, Jarheads, and Semper Fi. Each of these synonyms is used by both active and honorably discharged Marines as a sense of pride and respect. Whether you're discussing the history, training, or mission of the USMC, these synonyms add to the conversation and emphasize the importance of one of America's most elite protectors.