quemacatzin.

Headword: 
quemacatzin.
Principal English Translation: 

yes, affirming something (see Molina and Karttunen)

IPAspelling: 
keːmɑhkɑtsin
Alonso de Molina: 

quemacatzin. si. afirmando algo.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 88v. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

QUĒMAHCATZIN yes / si, afirmando algo (M) [(2)Cf.110v,125r,(2)Zp.115,184] According to C this is yet more reverential than QUĒMAHCA.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 208.

Attestations from sources in Spanish: 

Quemacatzin = sí
Antonio Vázquez Gastelu, Arte de lengua mexicana (Puebla de los Angeles, México: Imprenta Nueva de Diego Fernández de León, 1689), 33v.