Principal English Translation: 

a tomato, a type of fruit that goes into stews and sauces (see Molina and Karttunen)

Orthographic Variants: 
Alonso de Molina: 

Tomatl. cierta fruta que sirue de agraz en los guisados o salsas.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 149r. col. 1. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

TOMA-TL pl: -MEH tomato / cierta fruta que sirve de agraz en los guisados o salsas (M), tomate (T) The large red tomato is specifically named XĪTOMA-TL. In general, unmodified TOMA-TL refers to the green husk tomato.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 245.

Attestations from sources in English: 

Tomanamacac: quinamaca in xitomatl, in miltomatl, in izoatomatl, in tomapitzaoac, in tzopelic, in coaxitomatl, in chichioalxitomatl, in coatomatl, no quinamaca in coiotomatl, in xaltotomatl, in xaltomatl, coztic, cozpatic, cozpiltic, chichiltic, chilpatic, tlammilectic, tlatlapatic, chichilpatic, tlappatic, tlauizcaltic. = The tomato seller sells large tomatoes, small tomatoes, leaf tomatoes, thin tomatoes, sweet tomatoes, large serpent tomatoes, nipple-shaped tomatoes, serpent tomatoes. Also he sells coyote tomatoes, sand tomatoes, those which are yellow, very yellow, quite yellow, red, very red, quite ruddy, ruddy, bright red, reddish, rosy dawn colored. (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), 68.

Auh ca nohuian quihualtocatiaque yn tlalli. auh yn quihualquitiaque. yn intech monequia. nacatl yn tonacayotl. yhua yn etl. huauhtli. chian yhuan chilli. xitomatl = And everywhere they sowed seeds in the soil, and they ate what they needed: meat and the products of the lands [like] corn, beans, amaranth, chia, chilis, and tomatoes (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. 1, 76–77.

In the long discussion of different types of tomatoes in the writings of Dr. Francisco Hernández, we see the -me plural ending used, something originally reserved for animates. See for example, xitomame (which is "tomame with the shape of a rough squash"); miltomame (the planting type); coatomame ("snake tomatoes"). (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 the riddles found in the Florentine Codex. The tomato that wears a "shirt" (huipilli) might refer to the tomatillo with the paper-like, external shell: Zazan tleino, huipiltitich. Tomatl. = What is it that has a shirt stuck to it? The green tomato. (central Mexico, sixteenth century)
Thelma D. Sullivan, "Nahuatl Proverbs, Conundrums, and Metaphors, Collected by Sahagún," Estudios de Cultura Náhuatl 4 (1963), 133–134.