We talking Wicca? The Goddess is named Goddess, and the God is called God.
The Goddess is known as the Triple Goddess, Maiden, Mother, Crone, and Lady [some people call her Mother Earth, but its not universal.] People sometimes associate her with goddesses from other religions with similar attributes [such as Isis] but she doesn't have a name like 'Sarah' or something, its Goddess.
The God is similar, he has no real name, but he is know has the Horned or Stag God, Lord, The Green Man, or the Oak and Holly Kings. Granted those are tales used in conjunction with the God, but it is used to represent him.