The Collaborative International Dictionary of English v.0.48:

Halcyon \Hal"cy*on\ (h[a^]l"s[i^]*[o^]n), n. [L. halcyon,
   alcyon, Gr. "alkyw`n, 'alkyw`n: cf. F. halcyon.] (Zool.)
   A kingfisher. By modern ornithologists restricted to a genus
   including a limited number of species having omnivorous
   habits, as the sacred kingfisher (Halcyon sancta) of
   Australia.
   [1913 Webster]

         Amidst our arms as quiet you shall be
         As halcyons brooding on a winter sea.    --Dryden.
   [1913 Webster]