Tlaloc.

Headword: 
Tlaloc.
Principal English Translation: 

the deity associated with water, rain, and storms; or, a priest associated with water (see Karttunen and attestations)

IPAspelling: 
tɬɑːlok
Frances Karttunen: 

TLĀLOC personal name; pl: TLĀLOHQUEH Tlaloc, the god of water and rain; the host of rain gods (plural) / dios del agua o de la lluvia (S), los dioses del agua (C for plural) [(1)Bf.10r, (1)Cf.112v]. The derivation of this name is unclear. The singular form, which is the personal name of one deity, is not related in a regular way to the plural form, which refers to the company of rain gods. The plural form could be based on TLĀLLOH ‘something covered with earth’ if geminate reduction were to apply, reducing the LL to L, but the final –C of the singular would remain unaccounted for.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 276.

Attestations from sources in English: 

Mā tlaōcoya in amoyōlloh in amihtic oncah, in anTlāloqueh = Let your hearts which are within you be sad, you Tlalocs [i.e., mountains]
(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), 100.

Tlā xihuiquih, in antlamacazqueh, in anTlāloqueh, in nāuhcāmpa amonoqueh, in nāuhcāmpa acateh, in amilhuicaquītzquihtoqueh = Come, you who are priests, you who are Tlalocs, you who are lying there toward the four directions, you who are toward the four directions, you who lie gripping the sky [i.e., the mountains]. (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), 99.

plural = Tlalohqueh
Philip P. Arnold, Eating Landscape: Aztec and European Occupation of Tlalocan (Boulder: University Press of Colorado, 2001), 35.

mitoaia tlaloque intech tlamiloya yehoan quichiva in quiavitl = they were called Tlalocs because of them it was supposed that they made rain.
Fray Bernardino de Sahagún, Primeros Memoriales, ed. Thelma D. Sullivan, et al. (Norman: University of Oklahoma Press, 1997), 114.

In icoac tepeticpac moloni, momoloca, motlatlalia, mopiloa: mitoaia, ca ie uitze in tlaloque, ie quiiauiz, ie pixauizque in aoaque. = When clouds billowed and formed thunderheads, and settled and hung about the mountain tops, it was said: “The Tlalocs are already coming. Now it will rain. Now the masters of the rain will sprinkle water."
Todd Olson, "Clouds and Rain," Representations 104:1 (Fall 2008), 102–115; quote, from the Florentine Codex, appears on 102.

qujtlatlauhtiaia in tlaloc: in jtech qujtlamjaia qujavitl: iuh qujtoaia ca iehoatl vmpa tlatocatia in tlallocan in juhq'ma parayso terrenal ipan qujmatia = they prayed to Tlaloc, to whom they attributed the rain. They said that he governed Tlalocan, which they considered as an earthly paradise (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), 35.

The Atlcahualo (ceasing of water, rain), was the name of the first festival of the year. The ceremonies practiced at this time were meant to ensure the rains would come again. They included the sacrifice of small children, preferably children with two cowlicks in their hair, considered like whirlpools, and sometimes called "banderas humanas." The children would be sacrificed atop hills or mountains associated with the tlaloque (Tláloc deities). Other tlaloque are Nappatecuhtli, Opochtli, Tomiyauhtecuhtli (one of the four hundred rabbits that were deities of pulque), and the tepictoton, small legless figures.
Bernardo Ortiz de Montellano, "Las hierbas de Tláloc," Estudios de cultura náhuatl 14 (1980), 287–314, see p. 290.

Tlaloc, tlamacazquj: ynjn ipan machoia, in qujiaujtl: ca iehoatl quiiocoaia, qujtemoujaia, qujpixoaia, in quijaujtl, yoan in teciujtl: quixotlaltiaja, qujtzmolinaltiaja, qujxoxuvialtiaja, quicueponaltiaja, quizcaltiaia in quaujtl, in çacatl, in tonacaiotl. Yoan no itech tlamjloia, in teilaqujliztli, in tlaujtequjliztli. Auh ynjc michichioaia, tlaixtlilpopotzalli, tlaixolhujllli, motliloçac, ixmjchioave, ixmichioauhio, auachxicole, aiauhxicole, aztatzone, chalchiuhcozque, poçulcaque, no tzitzile, aztapilpane. = Tlaloc the priest. To him was attributed the rain; for he made it, he caused it to come down, he scattered the rain like seed, and also the hail. He cause to sprout, to blossom, to leaf out, to bloom, to ripen, the trees, the plants, our food. And also by him were made floods of water and thunder-bolts. And he was thus decorated: his face was thickly painted black, his face was painted with liquid rubber; it was anointed with black; his face was {spotted} with {a paste of} amaranth seeds. He had a sleeveless cloud-jacket of netted fabric; he had a crown of heron feathers; he had a necklace of green stone jewels. He had foam sandals, and also rattles. He had a plaited-reed banner. (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), 2.

Attestations from sources in Spanish: 

de 1567 años . . . Tlaloc xihuitl = Año de 1567 . . . Año de Tlaloc. (ca. 1582, México)
Luis Reyes García, ¿Como te confundes? ¿Acaso no somos conquistados? Anales de Juan Bautista (México: Centro de Investigaciones y Estudios Superiores en Antropología Social, Biblioteca Lorenzo Boturini Insigne y Nacional Basílica de Guadalupe, 2001), 162–163.

IN OZTOCOHCOYOCO ICUIC /
EL CANTO DE OZTOCOHCOYOCO
Anhuiloa itech in oztotl
anhuiloa, cuica miac xochitl,
amontlahtlauhtilo quexquich ehecame,
itech in oztotl.
Ompa huilaloque ehecatzitzintin.
Mixpantzin ehecatzitzintin,
nican tlalpan tihualoque,
totlanquaquetza,
ticualica ce, ome tlahtlanexti,
ica ce, ome mapichtli xochitl,
tihualto tinochintin, tlahtlauhtico:
ica toteotzin Tlaloc
manquimoyahuitili
tepetl ihuan tepilhuantzitzihuan
¡anquexquich tlacatzitzintin,
anquexquich ehecatzitzintin!
=
Pasad al interior de la cueva,
pasad con muchas flores y cantos,
haced súplicas a todos los viento,
en el interior de la cueva.
Allí van entrando los venerados vientos.
Ante el rostro de los vientos,
aquí sobre la tierra vamos pasando,
nos ponemos de rodillas,
llevamos una, dos antorchas,
con uno, dos manojos de flores,
Venimos todos nosotros a hacer súplicas:
Que Tláloc nuestro dios
dé la lluvia al monte,
y a los hijitos de la gente,
¡Oh todos vosotros estimados señores!
¡Oh todos vosotros, venerados vientos! (s. XX)
Miguel León-Portilla, "Yancuic Tlahtolli: Palabra Nueva; Una antología de la literatura náhuatl contemporánea (Segunda Parte)," Estudios de Cultura Náhuatl 19 (1989), 361–405, ver 394–395.