Principal English Translation: 

slavery, servitude; work or servitude of slaves or vassals (see Molina)

Orthographic Variants: 
Alonso de Molina: 

tlacoyotl. trabajo o seruidumbre de esclauos o vasallos.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 118v. col. 1. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

ie intech ca in intlacoio, ie uicti, ie mecapalti, ie teitzcuinhoan, ie tetotolhoan = already servitude would be upon them. Already they wielded the hoe, they used the tump line; already they were [as] someone else's dogs, someone else's turkeys. (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 7 -- The Sun, Moon, and Stars, and the Binding of the Venus, No. 14, Part VIII, eds. and transl. Arthur J. O. Anderson and Charles E. Dibble (Santa Fe and Salt Lake City: School of American Research and the University of Utah, 1961), 24.