Principal English Translation: 


Orthographic Variants: 
homey, ume, onteme, ondeme, ohome
Alonso de Molina: 

ome. dos.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 76r. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

ŌME pl: OMENTIN ~ ŌMEMEH two / dos (M) Z has a single attestation of ŌMEN as a plural form, and C forms the plural of OMŌME 'twelve' by adding -N too. In compounds the final vowel is lost, and before nonlabial consonants there is nasal assimilation yielding the alternation ŌM- ~ ŌN-. B has an attestation of an honorific form in which a glottal stop intervenes between ŌME and -TZIN. See OM-.
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 178.

Lockhart’s Nahuatl as Written: 

two. in combined forms ōm-, ōn-. abs. pl. ōmen, ōmentin. 228
James Lockhart, Nahuatl as Written: Lessons in Older Written Nahuatl, with Copious Examples and Texts (Stanford: Stanford University Press and UCLA Latin American Studies, 2001), 228.

Attestations from sources in English: 

ohome tomin = two tomin (Tula, 1570)
John Frederick Schwaller, "Constitution of the Cofradía del Santíssimo Sacramento of Tula, Hidalgo, 1570," Estudios de Cultura Náhuatl 19 (1989), 222.

See also ontetl. (SW)

The orthographic variants ume, onteme, and ondeme are found in a colonial (seventeenth-century) Guatemalan music manuscript.
Fernando Horcasitas y Alfred Lemmon, "El Tratado de Santa Eulalia: un manuscrito musical náhuatl," Tlalocan 12 (1997), 90, 92.

yz ca[te?] yn imecava y to thomas yn [...]catyca chicuacemi y
çe tlacatl ytoca maria tlacu ynic umety ytoca marda xocu yniquety ayamo mocuatequia ytoca teycuh ynic navity camo mocuatequia teycuh ynic macuillty amo [c.q] ytoca necavall ynic chicuacemi [c s'] ytoca magdallena teya[...]pa = Here are the concubines of don Tomás [...] six of them. The first is named María Tlaco, the second is named Marta Xoco. The third, not yet baptized, is named Teicuh. The fourth, not baptized, is named Teicuh. The fifth, not baptized, is named Necahual. The sixth, baptized, is named Magdalena Teya[ca]pan. (Cuernavaca region, ca. 1540s)
The Book of Tributes: Early Sixteenth-Century Nahuatl Censuses from Morelos, ed. and transl. S. L. Cline, (Los Angeles: UCLA Latin American Center Publications, 1993), 110–111.

inic vppa oallaque, iehoatl in don hernando Cortes = The second time they came it was [with] don Hernando Cortes
James Lockhart, We People Here: Nahuatl Accounts of the Conquest of Mexico, Repertorium Columbianum v. 1 (Los Angeles: UCLA Center for Medieval and Renaissance Studies, 1993), 62.

We can see inic onpa, "the second time," spelled in various ways. (SW)

Omeme = two + (plural ending, originally for animates) = i.e. two people. (SW)

Attestations from sources in Spanish: 

Inic 10 tli 2 me = La doceava cosa (Coyoacán, 1624)
Vidas y bienes olvidados: Testamentos en náhuatl y castellano del siglo XVII, vol. 3, Teresa Rojas Rabiela, et al, eds. (México: CIESAS, 2002), 144–145.

ynopiluan omeme = mis hijos que son dos (Santa Bárbara Maxoxtlan, sin fecha)
Vidas y bienes olvidados: Testamentos indígenas novohispanos, vol. 1, Testamentos en castellano del siglo XVI y en náhuatl y castellano de Ocotelulco de los siglos XVI y XVII, eds. Teresa Rojas Rabiela, Elsa Leticia Rea López, y Constantino Medina Lima (Mexico: CIESAS, 1999), 216–217.