tencualactli.

iztlactli tenqualactli, "drool + saliva = lies;"
See Sell's comments in Bartolomé de Alva, A Guide to Confession Large and Small in the Mexican Language, 1634, eds. Barry D. Sell and John Frederick Schwaller, with Lu Ann Homza (Norman: University of Oklahoma Press, 1999), 22.

intenqualac pipilcativitz = their spittle hanging down (central Mexico, sixteenth century)
James Lockhart, We People Here: Nahuatl Accounts of the Conquest of Mexico, Repertorium Columbianum v. 1 (Los Angeles: UCLA Center for Medieval and Renaissance Studies, 1993), 96.

Iztlactli, tenqualactli. Inin tlatolli, yehoatl quitoznequi in iztlacatiliztli, in amo neltiliztli: itechpa mitoaya in aquin tlatoani, anozo pilli, in zan muchi uel quineltoca, anozo quicaqui in iztlacatiliztli: ic iluiloya in iztlacatini: macamo iztlactli, tenqualacatili, in xiquito, in ixpan tlatoani: uel xictemo, uel xiquitta = Saliva, spittle. These words mean falsehood and untruth. It was said to the king or noble who believed all the lies he heard. "Do not tell lies or falsehoods in the presence of the king," the liar was told. "Investigate it thoroughly, look at it closely." (sixteenth century, central Mexico)
Thelma D. Sullivan, "Nahuatl Proverbs, Conundrums, and Metaphors, Collected by Sahagún," Estudios de Cultura Náhuatl 4 (1963), 158–159.