Irish altra

← Proto-Celtic *altrawū (inherited)

← Proto-Celtic *aleti (mention)

← Proto-Celtic *awū (mention)

← Welsh athro (cognate)

← Proto-Indo-European *h₂el- (root)

← Proto-Indo-European *h₂el- (derived)

← Proto-Indo-European *h₂éwh₂os (derived)

← Middle Irish altra (inherited)