1) a sardius, a precious stone of which there are two types, the former is called a carnelian (because flesh coloured) and the latter a sard
Part of Speech: adjective
Proper adjective from an uncertain base; sardian (G3037 being implied), that is, (as noun) the gem so called: - sardius.
These two sites give similar information, with the definition from several dictionaries and statistics on the use of the word.
Perseus Digital Library
University of Chicago's Logion lexicon
Thayer's dictionary plus other information.
From this site's dictionary (in Italian)
Click on the first column to search for that word as a form of the root σάρδιον; click on the second column to search for that grammatical form of the root σάρδιον; click on the third column to search for that word and grammatical form; click on the total to search for the root σάρδιον.