Angus and Malcolm Young were originally going to call their band Velvet Underground, or Tobacco Road, but these names had already been taken. They also considered using Lady Jane, The Escorts, and Teenage Rockers.
One day, their sister, Margaret, was sewing "AC/DC" on Angus' new sewing machine. Malcolm Young saw it and said "That's it!" because it referred to the alternating current-direct current power supply.