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1. The purest and most concentrated essence of something
    
2. The most typical example or representative of a type
    
3. (cosmology) the theory that the dark energy in the universe may be due to a scalar field and evolving with time
    
4. [archaic] The fifth and highest element after air and earth and fire and water; was believed to be the substance composing all heavenly bodies
   - ether [archaic]

Derived forms: quintessences

Type of: center [US], centre [Brit, Cdn], core, element, essence, example, exemplum, gist, heart, heart and soul, illustration, instance, inwardness, kernel, marrow, meat, nitty-gritty, nub, pith, representative, substance, sum

Encyclopedia: Quintessence