Principal English Translation: 

a silk cotton tree (Ceiba pentandra), a "large and beautiful" tree (see Molina and Karttunen)

Orthographic Variants: 
puchotl, pochotli
Alonso de Molina: 

puchotl. cierto arbol hermoso y grande.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 83v. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

PŌCHŌ-TL silk-cotton tree / árbol hermoso y grande, de cuyas raíces se sacaba un jugo que se utilizaba como febrífugo (S), árbol grande (C) [(1)Bf.4r(I)Cf.121r].
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 200.

Attestations from sources in English: 

pochotl (noun) = the ceiba tree; fig., protector, chief
Daniel Garrison Brinton, Ancient Nahuatl Poetry: Containing the Nahuatl Text of XXVII Ancient Mexican Poems (1877), 160.

Auh yhuan ye nauhpohualxihuitl. ypan nauhxivitl yn ipan 7. calli xihuitl. 1525. años. yn omomiquillico. yn tlacatl Don hernando quauhtimoctzin. çan quĩpilloque ytech pochotl ynehuan yn Don Pọ tetlepanquetzatzin tlahtohuani tlacupa. = And also, it was 84 years ago, in the year 7 House, 1525, the lord don Hernando Quauhtemoctzin passed away; they hanged him from a silk-cotton tree along with don Pedro Tetlepanquetzatzin, ruler in Tacuba. (1608, Central Mexico)
Annals of His Time: Don Domingo de San Antón Muñón Chimalpahin Quauhtlehuanitzin, James Lockhart, Susan Schroeder, and Doris Namala, eds. and transl. (Stanford: Stanford University Press, 2006), 134–135.

iuqui uey aueuetl, uey pochotl ic tlatocati: yehica iuicpa uel netemachilotoc = he was like a great cypress, a great ceiba, because the people put their trust in him. Thelma D. Sullivan, "Nahuatl Proverbs, Conundrums, and Metaphors, Collected by Sahagún," Estudios de Cultura Náhuatl 4 (1963), 144–145.

Taken into Spanish as pochote. (SW)

pochoquauhtitech quinpilloque yn omentin tlahtoque = they hanged two rulers on a silk cotton tree
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, 38–39.

Taueuetl, in tipochotl motlan moceoualhuiz, in maceoalli = You are a great cypress and cieba: under you the people shall have cover, they shall have shade.
Thelma D. Sullivan, "Nahuatl Proverbs, Conundrums, and Metaphors, Collected by Sahagún," Estudios de Cultura Náhuatl 4 (1963), 160–161.

pochotl = ceiba; may also refer to the warrior king specifically (late sixteenth century, Tetzcoco?)
Ballads of the Lords of New Spain: The Codex Romances de los Señores de la Nueva España, transcribed and translated by John Bierhorst (Austin: University of Texas Press, 2009), 32.

in totechiuhcaoan, in vel vevetque, in vel ilamatque muchiuhtiuj: in vel ceoallotiuj, in vel malacaiotivi, in vevei puchotl, avevetl muchiuhtivi yn ointlannecalaqujloc: auh in amo ointlan cahaqujco in jmma, in jmjcxi: in oqujҫoҫoaco in jmahaz, in jncujtlapiltzin = These were our forefathers who lived as the really old men, the really old women, who went casting a shadow, who went providing shade, who went forming the great silk cotton trees, the cypresses for those who became their subjects. And they were the ones who went not hiding their hands, their feet; rather, those who went extending their wings, their tail feathers (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 6 -- Rhetoric and Moral Philosophy, No. 14, Part 7, 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), 137.