The Collaborative International Dictionary of English v.0.48:

Rigel \Ri"gel\, n. [Ar. rijl, properly, foot.] (Astron.)
   A fixed star of the first magnitude in the left foot of the
   constellation Orion. [Written also Regel.]
   [1913 Webster]

WordNet (r) 3.0 (2006):

Rigel
    n 1: the brightest star in Orion [syn: Rigel, Beta Orionis]

The Free On-line Dictionary of Computing (30 December 2018):

Rigel

   A database language?  Based on Pascal.  Listed by
   M.P. Atkinson & J.W. Schmidt in a tutorial presented in
   Zurich, 1989.

   (1994-10-28)