ostia toptli.

(a loanword from Spanish)

Headword: 
ostia toptli.
Principal English Translation: 

a chest where the "hosts" are kept in the church, referring to crackers (symbolizing Christ's body) consumed in communion (see Molina; partly a loanword from Spanish, ostia, host)

Alonso de Molina: 

ostia toptli. ostiario para ostias.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 78r. col. 1. Thanks to Joe Campbell for providing the transcription.