amatlacuilolmachiotiliztli.

Headword: 
amatlacuilolmachiotiliztli.
Principal English Translation: 

the sealing or stamping of a letter or a piece of writing (see Molina)

Alonso de Molina: 

amatlacuilolmachiotiliztli. selladura de carta o de 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.