Avada Kadawara (Killing the Curse)

 Type: Curse

 Pronounced: ah-VAH-dah keh-DAV-rah

 Description:

 Avada-Kadavara causes instant death. It is accompanied by a flash of green light and a rushing noise. There is no known antidote that can protect the victim from death, except for a romantic sacrifice. This is one of the three unforgivable curses.

 Harry Potter survived this spell several times, both because of his mother's sacrifice, because he was an accidental Horcrux, and because his wand and his enemy were made from the same core.

 Seen / Mentioned: Used by Tom Riddle to kill many of his victims without remorse.

 Etymology: Avada Kedavra is based on Aramaic אבַדָא כְּדַברָא, avada kedavra, meaning "let the thing perish".

 Avifors (Avifor spell)

 Avifors

 Type: Shapeshifting

 Pronounced: AH-vi-fors

 Description: Turns the target into a bird.

 Seen / Mentioned: Teaching in conversion class.

 Etymology: From Latin avis meaning "bird" and forma meaning "shape".

 Lesem Avifor)

 Avifors

 Type: Shapeshifting

 Pronounced: AH-vi-fors

 Description: Turns the target into a bird.

 Seen / Mentioned: Teaching in conversion class.

 Etymology: From Latin avis meaning "bird" and forma meaning "shape".

 Avenseguim

 Avenseguim

 Type: Charm

 Pronounced: ah-ven-SEH-gwim

 Description: Turns an object into a tracking device.

 Seen/Mentioned: In 1927, Newt Scamander used this spell to trace the origin of a feather—a clue found during his search for Porpentina Goldstein—to Joseph Cama, from whom the feather hat came.

 Etymology: The spell Avenseguim probably comes from a portmanteau of avens, a Latin adjective for "passion" or "lust" and seguir, a Spanish and Portuguese verb meaning "to follow," or alternatively from Catalan seguim, meaning "we." . To follow". Taken together, Avenseguim can be interpreted as "to follow eagerly", which correctly describes the behavior of a tracking device.

 Avis (Amazing Bird Spell)

 Avis

 Type: spell, talisman

 Pronounced: AH-viss

 Description: It evokes a flock of birds from the tip of a mace. When used in conjunction with Oppugno, it can be used offensively.

 Seen/Mentioned: Used by Mr. Ollivander in 1994 to test Victor Chrome's wand. It was also used aggressively by Hermione Granger against Ron Weasley.