to tell someone their faults to their face (see Molina)
IPAspelling:
iːʃmɑnkɑtokɑ
Alonso de Molina:
ixmancatoca. nite. (pret. oniteixmancatocac.) lo mesmo es que ixcomaca. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 45v. col. 2. Thanks to Joe Campbell for providing the transcription.