to do something for oneself or by oneself (see Molina)
Orthographic Variants:
nonquauia, nonquahuia, noncua huia, nonqua huia
Alonso de Molina:
nonquauia. nitla. (pret. onitlanonquaui.) hazer algo asolas o porsi. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 73v. col. 1. Thanks to Joe Campbell for providing the transcription.