Polish druh

← Czech druh (cognate)

← Proto-Balto-Slavic *draugás (derived)

← Proto-Indo-European *dʰrewgʰ- (derived)

← Proto-Slavic *drugъ (derived)

← Ukrainian друг (cognate)

← Old Polish drug (inherited)

← Old Polish druch (mention)

→ Polish druhna (suffix)

→ Polish drużka (suffix)