Showing speed, liveliness, and eagerness in action or response; prompt and animated.
From Latin alacer (lively, brisk, eager) plus -ous (suffix forming adjectives). Alacer may be related to alere (to nourish), suggesting vitality. The word evolved through Middle English and Old French.
Alacrity is famous—everyone uses it—but alacrious is its forgotten adjective twin that means 'full of alacrity,' and you almost never hear it even though it works perfectly!
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