The Brahma bull is associated with Hinduism as the epitome of the god by the same name. Dwayne "The Rock" Johnson has a Brahma bull's head tattooed on his right bicep. It relates to his astrological sign, Taurus.
According to Tattoo Easily, bull tattoos often signify courage and power. A Brahma bull tattoo doesn't necessarily follow a standard design. Typically though, the bull's forehead is prominent, and its eyes are either empty or lit with fire, as is the case with The Rock's tattoo.
Because the Brahma bull so closely represents Hindu beliefs, such tattoos are often seen as manifestations of creation. In fact, the fire in the bull's eyes relates to the halo of fire, the symbol of the cyclical nature of birth, life and death.
The bull is also the Zodiac sign for Taurus. This sign is often associated with stability and strength as well as stubbornness. However, the bull is sometimes associated with the sun and thunder.
Different cultures have myths attached to bull tattoos. In Mediterranean cultures, bulls signify prosperity. Celts attached importance to cattle, and the bull became a symbol of reproduction and potency. Bull tattoos often look aggressive, which relates to their fury at the color red. Bulls also have a long tradition in Spain with bull fighting.