Principal English Translation: 

Mourning Dove, a bird (see Hunn, attestations); also, a person's name

Orthographic Variants: 
Alonso de Molina: 

uilotl. paloma.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 157v. col. 1. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

HUĪLŌ-TL pl: –MEH dove, pigeon / paloma (M).
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 90.

Attestations from sources in English: 

HUĪLŌ-TL, onomatopoetic, Mourning Dove (Zenaida macroura). [FC: 50-51 Vilotl] “It has a slender, pointed bill. It is chalky ashen. Its legs are like sticks.… The tail is long…. It is lazy. Its nest is only sticks which it places together; it piles a little grass on the surface…. And its habits are much like those of the cocotli. They are very attentive to their mates.… And if one dies, the one [remaining] always lives in mourning. And it seems constantly to weep; it makes [the sound] uilo-o-o. And its name, uilotl, is taken from its song, which says uilo.” This could only be the aptly named Mourning Dove.
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); 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analysis here also appearing in E. S. Hunn, "The Aztec Fascination with Birds: Deciphering Sixteenth-Century Sources," unpublished manuscript, 2022, cited here with permission.

in spiritu sancto in ipan omixeuhtzino in huilotl = the Holy Ghost, Who took the form of a dove (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, 160–161.

The mourning dove: "It is lazy. Its nest is only does not drink by day, only later. And it seems constantly to weep; it makes [the sound], uilo-o-o."
Henry M. Reeves, "Once Upon a Time in American Ornithology," The Wilson Journal of Ornithology 119:2 (June 2007), 315–318, quoting the Florentine Codex.

damiā huilotl (Tepetlaoztoc, sixteenth century)
Barbara J. Williams and H. R. Harvey, The Códice de Santa María Asunción: Facsimile and Commentary: Households and Lands in Sixteenth-Century Tepetlaoztoc (Salt Lake City: University of Utah Press, 1997), 88.

huilotl = mourning dove
Louise M. Burkhart, Before Guadalupe: The Virgin Mary in Early Colonial Nahuatl Literature, Institute for Mesoamerican Studies Monograph 13 (Albany: University at Albany, 2001), 52, note 46.

Attestations from sources in Spanish: 

huilotzi:n = huilotl
¿Tiguida ne huilotzi:n ijca:to ti:gni i:ten? = ¿Ves el pajarito que esta: parado en la ventana? (Sonsonate, El Salvador, Nahuat or Pipil, s. XX)
Tirso Canales, Nahuat (San Salvador: Universidad de El Salvador, Editorial Universitaria, 1996), 17–18.

See also: