- An undocumented hypothetical language from which all the Slavic languages later emerged.
- Common Slavic, Common Slavonic (more accurately referring to a late form of Proto-Slavic)
- Old Slavonic (may also refer to Old East Slavic or Old Church Slavonic)
Proto-Slavic (not comparable)
- Of or pertaining to the Proto-Slavic language
- Of or pertaining to the people or nation that spoke Proto-Slavic
of or pertaining to Proto-Slavic language or people who spoke it