milchilli.

Headword: 
milchilli.
Principal English Translation: 

a type of chile apparently cultivated in association with maize (hence the milli, or field, element) (Valley of Mexico, 1570–1587)
The Mexican Treasury: The Writings of Dr. Francisco Hernández, ed. Simon Varey, transl. Rafael Chabrán, Cynthia L. Chamberlin, and Simon Varey (Stanford: Stanford University Press, 2000), 110.

IPAspelling: 
miːltʃiːlli
Alonso de Molina: 

milchilli. axi que se haze enlas milpas o heredades.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 56v. col. 1. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

"milchilli . . . is usually planted and collected at the same time that corn is planted and harvested." (Central Mexico, 1571–1615)
The Mexican Treasury: The Writings of Dr. Francisco Hernández, ed. Simon Varey, transl. Rafael Chabrán, Cynthia L. Chamberlin, and Simon Varey (Stanford: Stanford University Press, 2000), 110.