macazotlein.

Headword: 
macazotlein.
Principal English Translation: 

do not let it be anything (see Molina)

IPAspelling: 
mɑːkɑsotɬein
Alonso de Molina: 

macazotlein. no sea nada.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 50r. col. 1. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

macazo tlein (negative) = no matter, for all that
Daniel Garrison Brinton, Ancient Nahuatl Poetry: Containing the Nahuatl Text of XXVII Ancient Mexican Poems (1877), 156.