Principal English Translation: 

to live; to dwell; to be; to go around, to go along; to walk; often seen at the end of a verb, with the effect of to go about doing that act

Alonso de Molina: 

nemi. ni. (pret. oninen.) biuir, o morar.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 67r. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

NEM(I) pret: NEN to live / vivir o morar (M) In compound constructions NEM(I) also has the sense 'to go about doing something,' but as a free form it is generally reduplicated, NEHNEM(I) 'to go along, to walk, to wander.' The preterit form contrasts in vowel length with NĒN ‘in vain.’
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 165.

Horacio Carochi / English: 

nemi = to live; to be; to go around; to go along
Horacio Carochi, S.J., Grammar of the Mexican language with an explanation of its adverbs (1645), translated and edited with commentary by James Lockhart, UCLA Latin American Studies Volume 89 (Stanford: Stanford University Press, UCLA Latin American Center Publications, 2001), 507.

Lockhart’s Nahuatl as Written: 

ni. to live, sometimes to be involved in something. Class 2: ōninen. as -ti- auxiliary verb, to go about doing something. sometimes has pluperfect nenca for pret., especially as auxiliary. 226
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), 226.

Attestations from sources in English: 

motolinitinenca = lived in misery
Fray Bernardino de Sahagún, Primeros Memoriales, ed. Thelma D. Sullivan, et al. (Norman: University of Oklahoma Press, 1997), 171.

quatro annos yn nemi = it is four years that he lives, or he is four years old
Sarah Cline, The Book of Tributes: The Cuernavaca-region Censuses, in James Lockhart, Lisa Sousa, and Stephanie Wood, eds., Sources and Methods for the Study of Postconquest Mesoamerican Ethnohistory (Eugene, OR: Wired Humanities Project, e-book, 2007.

Stem can change to nen- in the preterit.
eg. oninen = I lived
otinen = you lived
onen = s/he lived
otinenqueh = we lived
oannenqueh= you all lived
onenqueh = they lived
nenque = they went about

Attestations from sources in Spanish: 

quen tinemi = como te va
Pedro de Arenas, Vocabulario Manual de las Lenguas Castellana, y Mexicana (Mexico: Henrico Martínez, 1611), 1.

ylhuiloc yn testigo ya quexquich ica nemi = se le dijo al testigo, ya cuantos años tienes? (Tlaxcala, 1567)
Catálogo de documentos escritos en náhuatl, siglo XVI, vol. I (Tlaxcala: Gobierno del Estado de Tlaxcala y el Archivo Histórico del Estado de Tlaxcala, 2013), 64.macamo mochipa yc mochalanitinemizq = que no siempre vivan en desorden. (Tetzcoco, 1585)
Benjamin Daniel Johnson, “Transcripción de los documentos Nahuas de Tezcoco en los Papeles de la Embajada Americana resguardados en el Archivo Histórico de la Biblioteca Nacional de Antropología e Historia de México”, en Documentos nahuas de Tezcoco, Vol. 1, ed. Javier Eduardo Ramírez López (Texcoco: Diócesis de Texcoco, 2018), 94–95.

IDIEZ traduc. inglés: 
1. for an elderly person to continue to be active. 2. to do s.t. inappropriate.
IDIEZ def. náhuatl: 
1. ni. Tetahtzin zo tenantzin nocca quiza canahya. “Nototatah nocca nemi icelti pampa chicauhtoc. ” 2. ni. Macehualli zo tlapiyalli quichihua ce tlamantli tlen axcualli neci. “Jaime quiillia Juan iconeuh quenque quennopa nemi pan tlaixpiyalli: tlan yohui monequi ma mihtoti huan axcanah ma tlaoni. ” 3. Motzonpepechhuilia ce tlachihualiztlahtolli iyollo ica tlamotzquiltihquetl ti3. Macehualli, tecuani zo tlapiyalli axcanah cehcotzin quichihua ce tlamantli. “Ana itatah zan campahueli cochtinemi pampa quitlatilqueh ichan. ”
IDIEZ def. español: 
A. ni. Una abuelita y un abuelo todavía sale en algun lugar. “Mi abuelo todavía camina porque tinen fuerzas”. B. Un abuelo que camina todavía.
IDIEZ gramática: 
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