the extinct language or languages of the Illyrians, generally regarded as a distinct branch of the Indo-European family
See Illyrian in American Heritage Dictionary 4
adjective
Of or relating to ancient Illyria or its peoples, languages, or cultures.
noun
A member of one of the ancient peoples that inhabited Illyria.
An extinct Indo-European language spoken in Illyria and known only from scattered personal and geographical names preserved in Greek and Roman sources.