The state or quality of being exuberant; overflowing enthusiasm and liveliness.
A noun form created by adding the suffix -ness to exuberant, following the standard English pattern for creating abstract nouns from adjectives.
English gives us multiple words for the same concept (exuberance, exuberancy, exuberantness)—this shows how the language sometimes develops synonym stacks, each with slightly different historical origins.
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