tlanezcayotl.

This form in Laso de la Vego appears to be a mistake for nēzcāyōtl, sign, consisting of the preterit combining form of nēci and -yōtl; possibly the intention was itlah nēzcāyōtl.

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), 237.