temalacatl.

Headword: 
temalacatl.
Principal English Translation: 

circular, flat, sacrificial stone, the site for making offerings to the divinities
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2 -- The Ceremonies, no. 14, Part III, 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, 1951), 50.

Alonso de Molina: 

temalacatl. muela, o rueda de piedra.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 97r. col. 1. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

auh i yeuatl malli. niman ic quiuica in ompa miquiz temalacac icpac cantiuh contlehcauia, in oncan q'uahuanazqz malli. ymac concaua ytoca cuitlachueue. = And the captive he then took there where he was to die, upon the round sacrificial stone; he proceeded to take the captive by the head, and lead him up to there where they would slay him in the gladiatorial sacrifice. The one known as Old Wolf led him by the hand. (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 8 -- Kings and Lords, no. 14, Part IX, 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, 1951), 84.

cexiuhtica in quioalmattiuia: auh in ie isquich in omocemacico tlatoque, in quipachoa altepetl. Niman ie ic ompeoa, inic tlaoâoanoz temalacac: uel imispan mochioaia, uel quimittaia, in quezquitzontli mamalti miquia, auh no uel quimittaia, in aquin amo iollochicaoac, no uel quimittaia: in cequinti oc achiton ic oaltetlamauiçoltia, oalmoquichnenequi, cequintin oc oalmitotia = Once a year they came to witness it. And when all the rulers who governed cities had gathered together, thereupon began the gladiatorial sacrifice on the round sacrificial stone. Right before them it was performed; they could behold as many four hundreds as there were of captives slain. And also they could see those who were not stout of heart. Also they could see some who caused them somewhat to admire; who tried to be brave. Some still danced. (16th century, Mexico City)
Fray Bernardino de Sahagún, Florentine Codex, Book 9—The Merchants, trans. Charles E. Dubble and Arthur J.O. Anderson (Santa Fe, New Mexico; The School of American Research and the University of Utah, 1959), 6.

auh ynic mjtoaia quaujtl eoa: vncan necia, vncan onjxnecia, yn izqujntin oaoanozque temalacac: yoan in quexqujch çan miquiz, moteneoaia qujnquavitleoaltiaia yn oaoanti: vmpa ovico yiopico, yn iteupan Totec: vmpa qujntlaieecalviaia, in quenjn mizquizque, qujmeltequja: çan oc qujntlaiecultiaia: iotlaxcalli, anoço iopitlaxcalli, ynic qujmeletequja = And at the time called Quauitl eua, there on the round sacrificial stone appeared and came into view all those who were to be sacrificed victims. And of all those who were thus to die, it was said: “They raise poles for the striped ones.” They were brought to Yopico, [Xipe] Totec’s temple. There they made them fight in mock battle, in the same manner as they would later die, [when] they would tear their hearts out of them. They counterfeited this with them. [Using] tortillas of ground corn which had not been softened in lime [as mock-haters], they thus cut their hearts out. (16th century, Mexico City)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2—The Ceremonies, No. 14, Part III, 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, 1951), 44.

qujiaoaloa in temalacatl, yn oconiaoaloque, motlatlalia tecpantoque, ypan veuey icpalli, itoca quecholicpalli = they gathered around the circular, flat, sacrificial stone; they seated themselves according to rank on large chairs called quecholicpalli. (16th century, Mexico City)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2—The Ceremonies, No. 14, Part III, 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, 1951), 50.in ie iuhquj njman tlapitzalo, tecciztli mopitza, qujqujztli, mapipitzoa, yoan cujco: cujcapan tlapitzalpan, in oalmoiacatia: motecpana in cozcateca, qujquequechpanotiuj, aztapanjtl, qujiaoaloa in temalcatl = When this was done, then trumpets were sounded; conch shells, large sea shells, were blown; men put their fingers in their mouths and whistled, and there was singing. With singing of songs and blowing of trumpets, they arrived. The Cozcateca placed themselves in order, their shoulders decked with feather banners, and they encircled the offering-stone. (16th century, Mexico City)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2—The Ceremonies, No. 14, Part III, 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, 1951), 50.