The Collaborative International Dictionary of English v.0.48:

Zealous \Zeal"ous\ (?; 277), a. [LL. zelosus. See Zeal.]
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   1. Filled with, or characterized by, zeal; warmly engaged, or
      ardent, in behalf of an object.
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            He may be zealous in the salvation of souls. --Law.
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   2. Filled with religious zeal. [Obs.] --Shak.
      [1913 Webster] -- Zeal"ous*ly, adv. -- Zeal"ous*ness,
      n.
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