The quality of being exuberant; overflowing with enthusiasm, energy, and joy.
From Latin 'exuberare' (ex- 'out' + uberare 'to be fruitful, abundant'), this noun form emerged in English to describe an abundant, overflowing state of high spirits.
Exuberancy is the noun form of exuberant, and it captures that almost-too-much enthusiasm you see in very young kids before the world tells them to calm down.
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