Source : Webster's Revised Unabridged Dictionary (1913)

Sardius \Sar"di*us\, n. [L. sardius, lapis sardinus, Gr. ?, ?,
   ?. See {Sard}.]
   A precious stone, probably a carnelian, one of which was set
   in Aaron's breastplate. --Ex. xxviii. 17.

Source : WordNet®

sardius
     n : a deep orange-red variety of chalcedony [syn: {sard}, {sardine}]