köken: Etymology tree Proto-Indo-European *h₃er- Proto-Indo-European *h₃royH-keh₂ Proto-Balto-Slavic *raikāˀ Proto-Slavic *rěka Old Polish rzeka Polish rzeka Proto-Indo-European *-nós Proto-Balto-Slavic *-inas Proto-Slavic *-ьnъ Old Polish -ny Polish -ny Polish rzeczny From rzeka + -ny.
köken: Etymology tree Slovak rieka Proto-Indo-European *-nós Proto-Balto-Slavic *-inas Proto-Slavic *-ьnъ Old Slovak -ný Slovak -ný Slovak riečny From rieka + -ný.