namaca.

Headword: 
namaca.
Principal English Translation: 

to sell something (see Molina and Karttunen); referring to workers, "hire out" is a better translation; originally meant to give in return (see Lockhart)

IPAspelling: 
nɑmɑkɑ
Alonso de Molina: 

namaca. nitla. (pret. onitlanamacac.) vender algo.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 062v. col. 1. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

NAMACA vt to sell something / vender algo (M) This verb commonly incorporates objects, yielding such constructions as OCNAMACA 'to sell pulque/ ĒLŌNAMACA 'to sell corn,’ etc. NAMAQUILIĀ applic. NAMACA. NAMACALŌ altern. nonact. NAMACANAMACŌ altern. nonact. NAMACA .
NAHNAMACA redup. NAMACA.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 158.

Lockhart’s Nahuatl as Written: 

Class 1: ōnicmacac. originally na- reciprocal prefix added to maca. 226
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), 226.

Attestations from sources in English: 

hau yntla onpa namacoz cuetlaxcouapan= and if he is hired out in Puebla
Beyond the Codices, eds. Arthur J.O. Anderson, Frances Berdan, and James Lockhart (Los Angeles: UCLA Latin American Center, 1976), Doc. 1, 118–119.

originally meant to give in return
James Lockhart, The Nahuas after the Conquest: A Social and Cultural History of the Indians of Central Mexico, Sixteenth through Eighteenth Centuries (Stanford: Stanford University Press, 1992), 153.

When discussing workers, the verb can mean to "hire out," not necessarily "sell," as in a slave.
Beyond the Codices, eds. Arthur J.O. Anderson, Frances Berdan, and James Lockhart (Los Angeles: UCLA Latin American Center, 1976), 118, note 2.

Attestations from sources in Spanish: 

ycnotlacatl ycnopipiltotonti oquinnamacazquia llicendo Valdes ychan españoles mamatacti reales yca oticmaquixtique yxpan Valdes tevantin tiytlavan = El licenciado Valdés hubiera vendido a los hombres pobres y a los huérfanos a las fincas de los españoles por diez reales cada uno, pero nosotros, sus vasallos, los liberamos con esa [cantidad]
Nuestro pesar, nuestra aflicción / tunetuliniliz, tucucuca; Memorias en lengua náhuatl enviadas a Felipe II por indígenas del Valle de Guatemala hacia 1572, introduction by Cristopher H. Lutz, paleography and translation by Karen Dakin (México: UNAM and Centro de Investigaciones Regionales de Mesoamérica, 1996, 40–41.

themes: 
Markets, Commerce, Economy