USMC Devil Dog (USMC) The USMC Devil Dog is a nickname for members of the United States Marine Corps, derived from their combat tactics during the Battle of Belleau Wood in 1918. This moniker symbolizes the tenacity and ferocity that Marines are expected to exhibit on the battlefield. The term "Devil Dog" has since been officially adopted as a badge of honor within the Marine Corps. The iconic image of a growling dog's head with a devilish grin is often associated with the Devil Dog, which appears on various Marine Corps insignia and memorabilia. The USMC Devil Dog symbol represents the courage, discipline, and unyielding spirit that define members of the United States Marine Corps.