←
Proto-Indo-European *deh₃- (root)
←
Proto-Indo-European *déh₃nom (inherited)
←
Proto-Indo-European *deh₃- (mention)
←
Proto-Italic *dōnom (inherited)
→
Old French don (inherited)
→
Old French dun (inherited)
→
Galician doa (inherited)
→
Portuguese dom (derived)