The Collaborative International Dictionary of English v.0.48:

Sprightful \Spright"ful\ (-f[.u]l), a. [Spright sprite + full.]
   Full of spirit or of life; spirited; earnest; vivacious;
   lively; brisk; nimble; gay. [Obs.] -- Spright"ful*ly, adv.
   [Obs.] --Shak.
   [1913 Webster] -- Spright"ful*ness, n. [Obs.]
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         Spoke like a sprightful noble gentleman. --Shak.
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         Steeds sprightful as the light.          --Cowley.
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