Earrings were pieces of jewelry worn by both women and men. Women were more likely to wear them, but some males such as pirates frequently wore at least one.
Verne Brown wanted an earring, but Clara forbade it. When he and Marty McFly took the DeLorean to 1697, he sought out a tattoo artist in the Caribbean Islands to obtain an earring. Only once seeing how painful insertion of the earring would be, Verne backed out.