tlaca.

Headword: 
tlaca.
Principal English Translation: 

by day, daytime, midday

Orthographic Variants: 
tlacah
IPAspelling: 
tɬɑhkɑh
Alonso de Molina: 

tlaca. de dia, o personas.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 114v. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

TLAHCAH at midday / de día (M) M combines this in a single entry with TLĀCAH, the plural form of TLĀCA-TL ‘person.’ TLAHCAH also contrasts with TLACAH ‘that is to say.’ See TLAHCAH-TLI.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 259.

Horacio Carochi / English: 

tlàcâ = in the daytime
Horacio Carochi, S.J., Grammar of the Mexican language with an explanation of its adverbs (1645), translated and edited with commentary by James Lockhart, UCLA Latin American Studies Volume 89 (Stanford: Stanford University Press, UCLA Latin American Center Publications, 2001), 513.

Lockhart’s Nahuatl as Written: 

particle. in full day (late morning), toward midday.
James Lockhart, Nahuatl as Written: Lessons in Older Written Nahuatl, with Copious Examples and Texts (Stanford: Stanford University Press and UCLA Latin American Studies, 2001), 235.

Attestations from sources in English: 

quioallaça in tetl, in mitl, = hurried down stones and arrows (Mexico, Mid Sixteenth Century)
James Lockhart, We People Here: Nahuatl Accounts of the Conquest of Mexico, Repertorium Columbianum v. 1 (Los Angeles: UCLA Center for Medieval and Renaissance Studies, 1993), 220.

ye tlaca = it's late
Robert Haskett and Stephanie Wood's notes from Nahuatl sessions with James Lockhart and subsequent research.

vme vepantli quitlecavica, yoan miec in aoaquavitl, mimimiltic; itoca, teuquavitl in quitlecavique, in impan quioallaçazquia = they took up two large beams and many round oak logs called "god wood" that they were going to hurl down on [the Spaniards].
Mexico City, sixteenth century) James Lockhart, We People Here: Nahuatl Accounts of the Conquest of Mexico, Repertorium Columbianum v. 1 (Los Angeles: UCLA Center for Medieval and Renaissance Studies, 1993), 146.