Principal English Translation: 


Frances Karttunen: 

-TECHCOPA compound postposition concerning / de, acerca de (C) [(2)Cf.2or]. See -TECH, -COPA.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 216.

Horacio Carochi / English: 

-techcopa = concerning
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), 512, and see 84–85.

Lockhart’s Nahuatl as Written: 

relational word. relating to, about, concerning. -tech, -copa.
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), 232.