νεφρ-ός · nephr-os — LSJ
kidneys, Diog.Apoll. 6, Hp. Aph. 4.78, Pl. Ti. 91a, etc.: in dual, Ar. Ra. 475: rarely in sg., Id. Lys. 962, Euphro 1.25: euphem. for ὄρχεις, Philippid. 5.4: metaph., LXX Ps. 15(16).7. (Cf. OHG. nioro ‘kidney’, Praenest. nefrones, Lanuv. nebrundines ‘kidneys’, ‘testicles’.)