All 5 Uses

Hades
in
The Sea of Monsters
(Auto-generated)

The "Big Three" gods-Zeus, Poseidon, and Hades-had made a pact after World War II not to have any more children with mortals.†
Chpt 5 *

Hades = Greek mythology: the god of the underworld (land of the dead)
And Hades being under Los Angeles.†
Chpt 7
Lining the deck were zombies in gray uniformsdead soldiers with shimmering faces that only partially covered their skulls, like the ghouls I'd seen in the Underworld guarding Hades's palace.†
Chpt 10
That's the real reason Zeus, Poseidon, and Hades swore a pact after World War II not to have any more kids.†
Chpt 12
That's when all Hades broke loose.†
Chpt 18

Definitions:

(1) (Hades as in: the Olympian god)
Greek mythology: the god of the underworld (land of the dead); brother of Zeus and Poseidon
(2) (meaning too rare to warrant focus)
Hades was also the name of the Greek underworld (where the souls of the dead were thought to dwell). It is also used as a more polite way of saying hell.