quetzaltototl.

Headword: 
quetzaltototl.
Principal English Translation: 

the quetzal bird, prized for its long green feathers; this word can also stand for the feathers themselves; typically, the birds and the feathers were obtained through trade/tributes from peoples in Central America

For a beautiful photo of a quetzaltototl, see this one hosted by Mexicolore:
https://www.mexicolore.co.uk/images-6/613_01_2.jpg

Alonso de Molina: 

quetzaltototl. paxaro de plumas verdes muy ricas y estimadas.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 89r. col. 2. Thanks to Joe Campbell for providing the transcription.

Attestations from sources in English: 

QUETZAL-TŌTŌ-TL, Resplendent Quetzal (Pharomachrus mocinno) [FC: 19 Quetzaltototl]: This can only be the Resplendent Quetzal. QUETZAL-LI refers to the “plumage of the quetzal bird” (Karttunen).
Fr. Bernardino ]de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 11 – Earthly Things, no. 14, Part XII, 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, 1963); Frances Karttunen, An Analytical Dictionary of Nahuatl (University of Oklahoma, Norman, 1983); and, with quotation selections, synthesis, and analysis here also appearing in E. S. Hunn, "The Aztec Fascination with Birds: Deciphering Sixteenth-Century Sources," unpublished manuscript, 2022, cited here with permission.

quetzaltototl = a quetzal bird
Louise M. Burkhart, Before Guadalupe: The Virgin Mary in Early Colonial Nahuatl Literature, Institute for Mesoamerican Studies Monograph 13 (Albany: University at Albany, 2001), 43.

Auh ixqujch nenca in tlaҫotototl, y xiuhtototl, in quetzaltototl, i ҫaqua, in tlauhquechol, yoan in ie ixqujch nepapan tototl in cenca vel tlatoa, in vel tepacic cujca = And there dwelt all [varieties of] birds of precious feather—the blue cotinga, the quetzal, the trupial, the red spoonbill, and all the different birds, which spoke very well; which sang right sweetly (central Mexico, sixteenth century)
Fr. Bernardino de Sahagún, Florentine Codex: General History of the Things of New Spain; Book 3 -- The Origin of the Gods, Part IV, 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, 1978), 14.

ilhuicac quetzaltototl oalmotitla in iuictzinco Dios inantzi = a heavenly quetzal bird was sent to God’s mother (late sixteenth century, Central Mexico)
Louise M. Burkhart, Before Guadalupe: The Virgin Mary in Early Colonial Nahuatl Literature, Institute for Mesoamerican Studies Monograph 13 (Albany: University at Albany, 2001), 43.

açan axcà ye quetzaltototl nicyaizcaltiquetl a = Laboriously I feed the quetzal bird.;
Q. n. oncã evac in tetomã, nitlacochtetometl. auh in axcã ye quetzaltototl ynic nitlazcaltia = This means there in Tetoman he rose. I am Tlacochtetometl. And now he is a quetzal bird; therefore I feed him.... Y yopuchi noteuh atlavaquetl, = Opochtli, my god, is Atlahua.
Bernardino de Sahagún, Primeros Memoriales, ed. Henry B. Nicholson (Norman: University of Oklahoma Press, 1997), 152.