tlacotiamictli.

Headword: 
tlacotiamictli.
Principal English Translation: 

an enslaved human being who is for sale; or, the business of trading in enslaved human beings (see Molina)

Alonso de Molina: 

tlacotiamictli. esclauo que se vende en almoneda, o trato y mercaduria de vender y comprar esclauos.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 119r. col. 1. Thanks to Joe Campbell for providing the transcription.