mecatia.

Headword: 
mecatia.
Principal English Translation: 

to live together, cohabit; to have a concubine; or, to provide oneself with cords (see Molina)

IPAspelling: 
mekɑtiɑ
Alonso de Molina: 

mecatia. nino. (pret. oninomecati) amancebarse. o proueerse de cordeles.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 55r. col. 1. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

Ca nicnocuita ca onaahuilen, ca nahui, in çihuatl, onicnomecati = I engaged in licentiousness, I cohabited with four women
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), 137.

Cvix otimomecati? Cuix otaàhuilnen? = Have you had concubines? Have you licentiously enjoyed yourself?
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), 103.

From mecatl, cord.

Attestations from sources in Spanish: 

Ca nicnocuita ca onaahuilen, ca nahui, in çihuatl, onicnomecati = he fornicado, teniendo parte con quarto mugeres
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), 136–137.

Cvix otimomecati? Cuix otaàhuilnen? = As estado amançebado, te as entregado a los vicios de la sensualidad, y deleyte carnal.
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), 102–103.