of the Trojan War who was killed by an arrow shot into his heel, his one vulnerable spot
Aelian an early third-century-CE Roman author who wrote sensational stories about strange events and miraculous occurrences and was best known for his book On the Nature of Animals
Agrippina the Younger an ambitious and bloodthirsty Roman empress who was Nero’s mother; she was so domineering toward her son that he ordered her killed.
ambrosia a food of the gods that can heal demigods if eaten in small doses; it tastes like the user’s favorite food
amphisbaena a snake with a head at each end, born from the blood that dripped from Medusa’s severed head
Anicetus Nero’s loyal servant, who carried out the order to kill Agrippina, Nero’s mother
Aphrodite Greek goddess of love and beauty. Roman form: Venus
Ares the Greek god of war; the son of Zeus and Hera. Roman form: Mars
Artemis the Greek goddess of the hunt and the moon; the daughter of Zeus and Leto, and the twin of Apollo. Roman form: Diana
Asclepius the god of medicine; son of Apollo; his temple was the healing center of ancient Greece
Athena the Greek goddess of wisdom. Roman form: Minerva
Athena Parthenos a forty-foot-tall statue of the goddess Athena that was once the central figure in the Parthenon of Athens. It currently stands on Half-Blood Hill at Camp Half-Blood.
Bacchus Roman god of wine and revelry; son of Jupiter. Greek form: Dionysus
Battle of Manhattan the climactic final battle of the Second Titan War
Benito Mussolini an Italian politician who became the leader of the National Fascist Party, a paramilitary organization. He ruled Italy from 1922 to 1943, first as a prime minister and then as a dictator.
boare Latin equivalent of boo
Boreas god of the North Wind
Caligula the nickname of the third of Rome’s emperors, Gaius Julius Caesar Augustus Germanicus, infamous for his cruelty and carnage during the four years he ruled, from 37 to 41 CE; he was assassinated by his own guard
Camp Half-Blood the training ground for Greek demigods, located in Long Island, New York
Camp Jupiter the training ground for Roman demigods, located in California, between the Oakland Hills and the Berkeley Hills
Celestial bronze a powerful magical metal used to create weapons wielded by Greek gods and their demigod children
Celtic relating to a group of Indo-European peoples identified by their cultural similarities and use of languages such as Irish, Scottish Gaelic, Welsh, and others, including pre-Roman Gaulish
centaur a race of creatures that is half human, half horse. They are excellent archers.
Chaos the first primordial deity and the creator of the universe; a shapeless void below even the depths of Tartarus
Cistern a refuge for dryads in Palm Springs, California
cohort a group of legionnaires
Commodus Lucius Aurelius Commodus was the son of Roman Emperor Marcus Aurelius; he became co-emperor when he was sixteen and emperor at eighteen, when his father died; he ruled from 177 to 192 CE and was megalomaniacal and corrupt; he considered himself the New Hercules and enjoyed killing animals and fighting gladiators at the Colosseum
Cumaean Sibyl an Oracle of Apollo from Cumae who collected her prophetic instructions for averting disaster in nine volumes but destroyed six of them when trying to sell them to Tarquinius Superbus of Rome
Cyclops (Cyclopes, pl.) a member of a primordial race of giants, each with a single eye in the middle of his or her forehead
cynocephalus (cynocephali, pl.) a being with a human body and a dog’s head
Daedalus a Greek demigod, the son of Athena and inventor of many things, including the Labyrinth, where the Minotaur (part man, part bull) was kept
Dante an Italian poet of the late Middle Ages who invented terza rima; author of The Divine Comedy, among other works
Daphne a beautiful naiad who attracted Apollo’s attention; she transformed into a laurel tree in order to escape him
Deimos Greek god of fear
Demeter the Greek goddess of agriculture; a daughter of the Titans Rhea and Kronos
denarius (denari, pl.) a unit of Roman currency
Diana the Roman goddess of the hunt and the moon; the daughter of Jupiter and Leto, and the twin of Apollo. Greek form: Artemis
Didyma the oracular shrine to Apollo in Miletus, a port city on the western coast of modern-day Turkey
dimachaerus (dimachaeri, pl.) a Roman gladiator trained to fight with two swords at once
Dionysus Greek god of wine and revelry; the son of Zeus. Roman form: Bacchus
drachma a unit of ancient Greek currency
drakon a gigantic yellow-and-green serpentlike monster, with frills around its neck, reptilian eyes, and huge talons; it spits poison
dryad a spirit (usually female) associated with a certain tree
Elysium the paradise