in quemman.

Headword: 
in quemman.
Principal English Translation: 

one time; sometimes; or, at times (adverb) (see Molina)

Alonso de Molina: 

in quemman. alguna vez, o algunas vezes o atiempos. aduerbio.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 39r. col. 2. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

in quemman = at the time when, Niccelīz in quēmman àciz = I'll receive him when he arrives (knowing that he will do so today)
Michel Launey, An Introduction to Classical Nahuatl, translated and adapted by Christopher MacKay (Cambridge: Cambridge University Press, 2011), 134.

themes: 
Time, Calendar, Frequency