In Greek mythology, Hades doesn't just refer to a person, but also a place. While *Hades* is the name of a god, it's also the name of the underworld, the realm of the dead. Therefore, the meaning depends on context.
* As a god: Hades refers to the god of the underworld, ruler of the dead, and brother of Zeus and Poseidon.
* As a place: Hades refers to the underworld itself, the shadowy realm where the souls of the deceased reside.