King's Cross Station: The train station in London from which the Hogwarts Express departs. Students boarding the train leave from Platform Nine and Three-Quarters.
Ministry of Magic: The British wizarding community's governing body. The ministry, headed by the Minister of Magic, keeps the wizarding world secret from Muggles.
Mudblood: Derogatory term used to describe someone born to nonmagical parents.
Muggle: A nonmagical person.
Parselmouth: A wizard who can talk to snakes in the language of Parseltongue. Many wizards take this as the mark of a Dark wizard.
Patronus: A positive force that is conjured in defense of a Dementor. A Patronus appears as a bright light that takes the form of a different animal for each wizard.
Quidditch: The beloved sport of the wizarding world. Quidditch is played on broomsticks and involves throwing balls through six big hoops. At the same time, a player on each team, called the Seeker, is trying to catch the Golden Snitch. When the Snitch is caught, the game is over.
Ravenclaw House: One of the four houses in Hogwarts. Students in Ravenclaw are characterized by wisdom, wit and love of learning.
Slytherin House: One of the four houses in Hogwarts. Students in Slytherin are characterized by ambition, cleverness and cunning.
Sorting Hat: The hat that each matriculating Hogwarts students wears when he first arrives. The hat decides to which of the four houses a student will belong.
Unforgivable Curses: The three most powerful and evil spells, used mostly by Dark wizards.
Weasleys' Wizard Wheezes: The joke shop that Fred and George Weasley open in Diagon Alley after graduating from Hogwarts.
Zonko's: The famous joke shop located in Hogsmeade.