köken: Inherited from Latin ambōs m pl. Old Spanish consistently had amos, representing the inherited form, while ambos existed in neighbouring Old Leonese. Later, Latin influence helped ambos spread into Spanish as well, where it displaced the form without /b/.
köken: Inherited from Vulgar Latin *amendoi, from ambī duī, from Latin ambō (“both”) + duī, from duo (“two”). Compare Aromanian amindoilji, andoilji. Cf. also Old Italian amendue, Engadine amenduos, Old French andui, Occitan amdui.
köken: From Old Danish bæggiæ, from Old Norse beggja, from Proto-Germanic *bajjǫ̂, the genitive form of Proto-Germanic *bai (“both”). In Old Norse the other cases have been replaced by the enlargened stem báðir (cf. Danish både).