to dare (confront) someone, going right up to their face (see Molina)
Orthographic Variants:
ixconeua
Alonso de Molina:
ixconeua. (pret. oixco neuh.) atreuerse a otro yendosele ala cara. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 45r. col. 1. Thanks to Joe Campbell for providing the transcription.