Nirtautas

Maybe from *Ner-nation. Although sandas nir- is also possible. For nir- (ner-) cf. Ave. Nir-gunde || Ner-gunde, Nyr-mede || Ner-mede, Nyr-ginde, Nir-glande, Nir-glinde; Ner-dingis, Ner-gaut ¹. For the nation - see Proliferative.