tlatzcan.

Headword: 
tlatzcan.
Principal English Translation: 

the cypress tree (see Molina)

IPAspelling: 
tɬɑtskɑn
Alonso de Molina: 

tlatzcan. cipres.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 142v. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

TLATZCAN cypress / ciprés (M), cedro o ciprés (C) This abundantly attested in C. It also appears in Z with the absolutive suffix -TLI, but this is idiosyncratic to Z.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 300.

Attestations from sources in English: 

"The Mexicans gave the name tlatzcan, or 'fragile and glassy wood,' to the tree that the ancients, Pliny among them, called the cypress...with the boughs extended sideways and almost inclining downward, from which its name comes." (Central Mexico, 1571–1615)
The Mexican Treasury: The Writings of Dr. Francisco Hernández, ed. Simon Varey, transl. Rafael Chabrán, Cynthia L. Chamberlin, and Simon Varey (Stanford: Stanford University Press, 2000), 127.

This is an example of a suffixless noun (no -tl, -tli, or -in ending).
Michel Launey, An Introduction to Classical Nahuatl, translated and adapted by Christopher MacKay (Cambridge: Cambridge University Press, 2011), 232.

Melton-Villanueva discusses the prevalence in Nahuatl testaments of the altepetl of San Bartolomé Tlatelolco, in the valley of Toluca, where people requested burial near the copal trees. Other "burial trees" were the cypress (tlatzcan), the date palm (icçotl, iczotl), and the pirul.
Miriam Melton-Villanueva, The Aztecs at Independence: Nahua Culture Makers in Central Mexico, 1799–1832 (Tucson: University of Arizona Press, 2016), 110.

themes: 
Plants, Trees, Flora
Wood, wooden material