mecapalli.

Headword: 
mecapalli.
Principal English Translation: 

tump line, a leather strap that runs across the forehead and down the back, for carrying loads; the paired phrase, "huictli mecapalli," the hoe, the tumpline, was a reference to the work of commoner males (see attestations)

IPAspelling: 
mekɑpɑlli
Alonso de Molina: 

mecapalli. mecapal, cordel para lleuar carga acuestas.
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.

Frances Karttunen: 

MECAPAL-LI pl: -MEH- -TIN tumpline, rig for carrying a load on the back supported by a band across the forehead / mecapal, cordel para llevar carga a cuestas (M) [(1)Cf. 103V, (2)Tp. 133, 141, (3)Xp. 52]. See MECA-TL, -PAL.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 142.

Attestations from sources in English: 

Cuix in, yquac aca omomiquili in àço mohuayolqui in áço, oc çe tlacatl, cuix Ayatl, piçietl, mecapilli, tomin, atl, tlaqualli, oanquihuicaltique, in ipan oanquitocaque, oanquiquimiloque in amo oquima in teopixqui? = When someone died- perhaps your relative or maybe some other person- did you accompany, bury and wrap each one of them up with henequen cloaks, tobacco, tumplines, sandals, money, water, food, [and all] unbeknownst to the priest?
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), 83.

njman ie ic qujmecapallotia, qujmemecapallotia = Thereupon they took up [each bundle] in a tump line; they took them up in tump lines. (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 2 -- The Ceremonies, no. 14, Part III, 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, 1951), 74.

mecapalnamacac in itequiuh melio = The tump-line sellers' tax is ½ tomín (Coyoacan, mid-sixteenth century)
Beyond the Codices, eds. Arthur J.O. Anderson, Frances Berdan, and James Lockhart (Los Angeles: UCLA Latin American Center, 1976), Doc. 25, 140–141.

cuix ic oppa niquittaz y nohuic y nomecapal = Am I a second time to look for my digging stick and my tump line? (central Mexico, early seventeenth century)
Codex Chimalpahin: Society and Politics in Mexico Tenochtitlan, Tlatelolco, Culhuacan, and Other Nahuatl Altepetl in Central Mexico; The Nahuatl and Spanish Annals and Accounts Collected and Recorded by don Domingo de San Antón Muñón Chimalpahin Quauhtlehuanitzin, eds. and transl. Arthur J. O. Anderson and Susan Schroeder (Norman: University of Oklahoma Press, 1997), vol. 2, 46–47.

Cioacoatl tequanj: yoan tetzaujtl, tetetzaujanj, icnoiutl qujteittitia: ca mjtoaia, victli mecapalli, qujtemacaia, ic temotlaia. = The savage Snake-woman (Ciuacoatl), ill-omened and dreadful, brought men misery. For it was said: “She giveth men the hoe and trump-line. Thus she forceth men {to work}.” (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 1 -- The Gods; No. 14, Part 2, 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, 1950), 3.

Attestations from sources in Spanish: 

Cuix in, yquac aca omomiquili in àço mohuayolqui in áço, oc çe tlacatl, cuix Ayatl, piçietl, mecapilli, tomin, atl, tlaqualli, oanquihuicaltique, in ipan oanquitocaque, oanquiquimiloque in amo oquima in teopixqui? = Por ventura quando murio alguno, o tu pariente, ò otro qualquiera enterrasteslo, echandole e la sepultura manta de Nequen, piciete, mecapal, çapatos, dineros, comida, y veuida, y todo á escusas de vuestro Ministro?
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), 82–83.