Old Irish áigthiu

← Proto-Celtic *āgetor (derived)

← Proto-Celtic *-tiū (derived)

← Proto-Celtic (mention)

← Proto-Indo-European *h₂eh₂ógʰe (derived)

← Proto-Indo-European *h₂egʰ- (mention)

← Proto-Indo-European *[[-tis|-ti]][[-Hō]] (derived)

← Latin -tiō (cognate)

← Old Irish ad·ágathar (mention)

← Old Irish -tiu (affix)