Quintessence comes from the Latin quinta essentia, literally meaning "fifth essence". Though the term can have a number of meanings, the most likely one being referred to here is the concept of a fifth classical element (the other four being air, water, fire, and earth) that makes up the regions of the universe beyond the terrestrial sphere. This element is more commonly referred to as æther, although different mythologies have differing standards, the Japanese godai, for example, designating it as the void, and the film "The Fifth Element" (1997) deeming it humanity.
- Harry Potter and the Half-Blood Prince (First appearance)
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