The House of Hades (The Heroes of Olympus #4)(147)

Mist a magic force that disguises things from mortals

Mount Tamalpais the site in the Bay Area (Northern California) where the Titans built a palace

naiads water nymphs

Necromanteion the Oracle of Death, or House of Hades in Greek; a multileveled temple where people went to consult with the dead

Neptune the Roman god of the sea. Greek form: Poseidon

New Rome a community near Camp Jupiter where demigods can live together in peace, without interference from mortals or monsters

Notus Greek god of the South Wind. Roman form: Auster

numina montanum Roman mountain god (montana, pl). Greek form: ourae

nymph a female nature deity who animates nature

nymphaeum a shrine to nymphs

Nyx goddess of night; one of the ancient, firstborn elemental gods

Odysseus legendary Greek king of Ithaca and the hero of Homer’s epic poem The Odyssey. Roman form: Ulysses

Ogygia the island home—and prison—of the nymph Calypso

ourae Greek for mountain god. Roman form: numina montanum

Ouranos father of the Titans

Pasiphaë the wife of Minos, cursed to fall in love with his prize bull and give birth to the Minotaur (part man, part bull); mistress of magical herbal arts

Pegasus in Greek mythology, a winged divine horse; sired by Poseidon, in his role as horse-god, and foaled by the Gorgon Medusa; the brother of Chrysaor

Periclymenus an Argonaut, the son of two demigods, and the grandson of Poseidon, who granted him the ability to change into various animals

peristyle entrance to an emperor’s private residence

Persephone the Greek queen of the Underworld; wife of Hades; daughter of Zeus and Demeter. Roman form: Proserpine

phalanx a compact body of heavily armed troops

Phlegethon the River of Fire that flows from Hades’s realm down into Tartarus; it keeps the wicked alive so they can endure the torments of the Fields of Punishment

pilum (pila, pl.) a javelin used by the Roman army

Pluto the Roman god of death and riches. Greek form: Hades

Polybotes the giant son of Gaea, the Earth Mother

Polyphemus the gigantic one-eyed son of Poseidon and Thoosa; one of the Cyclopes

Porphyrion the king of the giants in Greek and Roman mythology

Poseidon the Greek god of the sea; son of the Titans Kronos and Rhea, and brother of Zeus and Hades. Roman form: Neptune

praetor an elected Roman magistrate and commander of the army

Proserpine Roman queen of the Underworld. Greek form: Persephone

Psyche a young mortal woman who fell in love with Eros and was forced by his mother, Aphrodite, to earn her way back to him

quoits a game in which players toss hoops at a stake

Riptide the name of Percy Jackson’s sword; Anaklusmos in Greek

River Acheron the fifth river of the Underworld; the river of pain; the ultimate punishment for the souls of the damned

River Lethe one of several rivers in the Underworld; drinking from it will make someone forget his identity

Romulus and Remus the twin sons of Mars and the priestess Rhea Silvia. They were thrown into the River Tiber by their human father, Amulius, and were rescued and raised by a she-wolf. Upon reaching adulthood, they founded Rome.

Saturn the Roman god of agriculture; the son of Uranus and Gaea, and the father of Jupiter. Greek form: Kronos

satyr a Greek forest god, part goat and part man. Roman equivalent: faun

Scipio Reyna’s pegasus

Sciron an infamous robber who ambushed passersby and forced them to wash his feet as a toll. When they knelt, he kicked his victims into the sea, where they were eaten by a giant turtle.

scorpion ballista a Roman missile siege weapon that launches a large projectile at a distant target

Senatus Populusque Romanus (SPQR) meaning “The Senate and People of Rome,” it refers to the government of the Roman Republic and is used as an official emblem of Rome

shadow-travel a form of transportation that allows creatures of the Underworld and children of Hades to travel to any desired place on earth or in the Underworld, although it makes the user extremely fatigued

Sibylline Books a collection of prophecies in rhyme written in Greek. Tarquinius Superbus, a king of Rome, bought them from a prophetess named Sibyl and consulted them in times of great danger.

spatha a heavy sword used by Roman cavalry

Spes goddess of hope; the Feast of Spes, the Day of Hope, falls on August 1

stela (stelae, pl.) an inscribed stone used as a monument

Stygian iron a magical metal, forged in the River Styx, capable of absorbing the very essence of monsters and injuring mortals, gods, Titans, and giants. It has a significant effect on ghosts and creatures from the Underworld.

Tantalus In Greek mythology, this king was such a good friend of the gods that he was allowed to dine at their table—until he spilled their secrets on earth. He was sent to the Underworld, where his curse was to be stuck in a pool of water under a fruit tree, but never to be able to drink or eat.

Tartarus husband of Gaea; spirit of the abyss; father of the giants

telkhine a sea demon with flippers instead of hands, and a dog’s head

Tempest Jason’s friend; a storm spirit in the form of a horse

Terminus the Roman god of boundaries and landmarks

Terra the Roman goddess of the Earth. Greek form: Gaea

Thanatos the Greek god of death; servant of Hades. Roman form: Letus

Theseus a king of Athens who was known for many exploits, including killing the Minotaur