Principal English Translation:
a small hill; a temple or a pyramid (see Karttunen); something covered up or closed; enclosure; wall; fence
Orthographic Variants:
tlatzacualli, tlatzaqualli, tzaqualli, tetzacualli, tetzacualli tepantli, tzacuali, tzacoalli
Attestations from sources in English:
Mitoa in ascan, tetepe tzacuilli, itzacuil tonatiuh, yoan itzacoal metzli. = They are now called pyramids—the pyramid of the sun and the pyramid of the moon. [Dibble and Anderson translation.]
Florentine Codex, Book 7, Chapter 4.
auh neli melahuac. yninte tzacuali tepantli. = And it was certainly true that they made this great temple
Anónimo mexicano, ed. Richley H. Crapo and Bonnie Glass-Coffin (Logan, UT: Utah State University Press, 2005), 31.
itzacual tonatiuh = pyramid of the sun
Ronald W. Langacker, "Possessives in Classical Nahuatl," International Journal of American Linguistics 38:3 (July 1972), 173–186.
A glyph in the Codex Mendoza illuminates the term tzacualli: https://aztecglyphs.wired-humanities.org/content/tzacualpan
Attestations from sources in Spanish:
moxitiniz yn itlatzacual = que se derrueque e quite lo que tiene cercado (Ciudad de México, 1570)
Luis Reyes García, Eustaquio Celestino Solís, Armando Valencia Ríos, et al, Documentos nauas de la Ciudad de México del siglo XVI (México: Centro de Investigación y Estudios Superiores en Antropología Social y Archivo General de la Nación, 1996), 134.