to remove a seal from a letter or a piece of writing (see Molina)
Alonso de Molina:
amatlacuilolmachioana. n. (pret. onamatlacuilolmachioan.) quitar sello ala carta, o a otra escriptura. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 4v. col. 2. Thanks to Joe Campbell for providing the transcription.