Source : Webster's Revised Unabridged Dictionary (1913)

Ra \Ra\, n.
   A roe; a deer. [Obs.] --Chaucer.

Source : WordNet®

Ra
     n 1: an intensely radioactive metallic element that occurs in
          minute amounts in uranium ores [syn: {radium}, {atomic
          number 88}]
     2: (astronomy) the angular distance eastward along the
        celestial equator from the vernal equinox to the
        intersection of the hour circle that passes through the
        body; expressed in hours and minutes and second; used with
        declination to specify positions on the celestial sphere;
        "one hour of right ascension equals fifteen degrees" [syn:
         {right ascension}, {celestial longitude}]
     3: ancient hawk-headed Egyptian sun god; a universal creator
        [syn: {Re}]