Source : Webster's Revised Unabridged Dictionary (1913)

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}.]

Regel \Re"gel\ (r?"g?l), n. (Astron.)
   See {Rigel}.