The Collaborative International Dictionary of English v.0.48:
Ariel \A"ri*el\, n., or Ariel gazelle \A"ri*el ga*zelle"\ [Ar. aryil, ayyil, stag.] (Zool.) (a) A variety of the gazelle (Antilope dorcas, or Gazella, dorcas), found in Arabia and adjacent countries. (b) A squirrel-like Australian marsupial, a species of Petaurus. (c) A beautiful Brazilian toucan Ramphastos ariel). [1913 Webster]