picietl.

Headword: 
picietl.
Principal English Translation: 

tobacco, a plant that is "medicinal" (see Molina); also had a role in rituals (see Ruiz de Alarcón)

Alonso de Molina: 

picietl. yerua como veleño, que es medicinal.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 81v. col. 1. Thanks to Joe Campbell for providing the transcription.

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.

Picienamacac: quinamaca picietl, xicôiietl, tlalietl, quimaxaqualoa: in aca quitta picietl, quiqua. Auh cequintin iztauhiatl in quipiciepoa: in picietl tetech quiz, teiuinti, tetlatemouili, teciauizpôpolo. = The seller of fine tobacco sells fine tobacco..., small tobacco. He rubs it between his hands. He who finds fine tobacco chews it. And some prefer wormwood to tobacco. Fine tobacco affects one; it makes one drunk, it aids one's digestion, it dispels one's fatigue. (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 10 -- The People, No. 14, Part 11, 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), 94.

"...certain hollow pieces of cane, a span and a half in length, which on the outside are smeared with charcoal dust and on the inside are filled with tobacco and liquidambar (or xochiocotzotl), and also with other hot and aromatic things." (Central Mexico, 1571–1615)
The Mexican Treasury: The Writings of Dr. Francisco Hernández, ed. Simon Varey, transl. Rafael Chabrán, Cynthia L. Chamberlin, and Simon Varey (Stanford: Stanford University Press, 2000), 115.

In making an incantation for increasing the chance of catching fish with a hook, Juan Matheo of Comallan (district of Atenango), and others like him were said by Ruiz de Alarcón to make offerings and sacrifices to the fire or to the "piciete," "or to one of the idols of their heathenism, such as Quetzalcoatl or Xochiquetzal, etc."
Ruiz de Alarcón also states that they people who were fishing with fences and weirs would "prepare themselves with their venerated piciete, and they leave with it for the river...." (Atenango, between Mexico City and Acapulco, 1629)
Hernando Ruiz de Alarcón, Treatise on the Heathen Superstitions That Today Live Among the Indians Native to This New Spain, 1629, eds. and transl. J. Richard Andrews and Ross Hassig (Norman and London: University of Oklahoma Press, 1984), 117.

In Book 10 of the Florentine Codex, the image of the tobacco seller shows a woman selling and a man purchasing.
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 10 -- The People, No. 14, Part 11, 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), see image 148, which the translators link with the text in chapter 26.

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.

el tabaco (picietl) = un producto vegetal asociado con la religión y el sacerdocio
Bernardo Ortiz de Montellano, "Las hierbas de Tláloc," Estudios de cultura náhuatl 14 (1980), 287–314, ver la p. 290.