The brass knuckles tattoo means you’re bad to the bone. The brass knuckles tattoo can be paired with a broad range of imagery to embellish the tough-guy or tough-girl motif, such as razors and skulls and wolves and tigers. This tattoo design is also frequently accompanied by other symbols that can change the meaning of the tattoo. When paired with a heart, this tattoo design symbolizes tough love, or the dichotomy of love and hate. When paired with a military insignia or abbreviation of one of the branches of the military, it symbolizes service and patriotism. This design is ideal for the person who has been hardened by life and is proud of it. Brass knuckle tattoos are very popular with professional military and athletes. The design is also used sometimes with added imagery symbolizing a disease or disorder – to signify the everyday struggle of the afflicted. The origin of the tattoo is uncertain, but it has been prevalent for the past fifty or so years in the United States and Europe.