"You've found Thaumatagoria! I always thought it was a myth! A story told to excite potion-makers, to make them dream impossible dreams! The rumours about its properties are legendary, you wonderful, wonderful young potioneer!"
-- Zygmunt Budge (BoP)
thauma = Greek for "miracle, wonder", from which we also get the word "thaumaturge", meaning "a worker of wonders or performer of miracles, a magician." (Dictionary.com)
The name of this plant was difficult to understand from the audio of the game, but it was confirmed from "Book of Potions" Game Files by Harry Potter Wiki.
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