tlamacuilti.

Headword: 
tlamacuilti.
Principal English Translation: 

Thursday, the fifth day of the week (see Molina); also a 5-day period at the end of 20-day months (see Sahagún)

IPAspelling: 
tɬɑmɑːkwiːlti
Alonso de Molina: 

tlamacuilti. jueues, quinto dia dela semana.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 125v. col. 1. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

auh noviian qujtlalilia yn jchial, in mumuztli in vtlica, in vmaxac, noujian chialoia. Auh in mumuzco acxoiatl qujtlaliliaia, ynjc tlamacujlti ilhujtl, ynjc tzonqujҫa cempoalilhujtl: muchipa iuh muchiuhtiuja, yn jpan cecentetl ilhujtl, ynjc tlantiuh cecempoalilhujtl = And everywhere they set up his sanctuaries, shrines by the road, at crossroads. Everywhere he was awaited. And in the shrines they had fir branches laid on the five days with which the twenty-day [month] ended. Always they went to do this on each of the [five] days with which each month ended (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 3 -- The Origin of the Gods, Part IV, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1978), 12.