nen.

Headword: 
nen.
Principal English Translation: 

in vain, futilely, profitlessly, uselessly, for nothing (see Molina, Carochi/Lockhart, Karttunen, and Bierhorst)

Orthographic Variants: 
nēn
IPAspelling: 
nen
Alonso de Molina: 

nen. en vano, por demas, o sin prouecho. aduerbio.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 67v. col. 2. Thanks to Joe Campbell for providing the transcription.

Frances Karttunen: 

NEN in vain, futilely, profitlessly / en vano, por demás, o sin provecho (M) This commonly occurs bound with ZAN. It contrasts in vowel length with the preterit form of NEM(I).
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 166.

Horacio Carochi / English: 

nēn = in vain
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.

Attestations from sources in English: 

Nēn: "Adverbial particle expressing doubt or antiipating failure. In vain (MOL), uselessly (MOL); perchance (CAR 507:5), probably not, scarcely, hardly.
John Bierhorst, A Nahuatl-ENglish Dictionary and Concordance to the Cantares Mexicanos with Analytical Transcription and Grammatical Notes (1985), 233.

Auh ca amo çā nen. ca niquinpehuaz = And not for nothing shall I conquer them. (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, 78–79.

Onen oncatca. Iquac mitoa: intla itla oquinequia noyollo, zan amo uel omuchiuh. = It was in vain. This is said when I desire something with all my heart that cannot be done.
Thelma D. Sullivan, "Nahuatl Proverbs, Conundrums, and Metaphors, Collected by Sahagún," Estudios de Cultura Náhuatl 4 (1963), 108–109.

quẽ ҫan nel oc nen = What can be done? Is it yet in vain? (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), 84.

Auh in axcan: ça nen tiuhque, ça nen tehoan aiuhtlancaiutl, aiuhqujzqui popolonqui tzatzacquj, aitlaliloia, aitenqujxtiloian: ic toconcuepa, toconjlochia, in amjhijotzin, in amotlatoltzin = But now, thus are we useless; useless are we; unfinished, incomplete, stuttering, stammering, unsettled, unpronounced is that with which we return, with. which we respond to your discourse.
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), 138.

Attestations from sources in Spanish: 

amo tle nenpolihui = no se pierda nada inútilmente
El Libro de Testamentos de Culhuacán: Vida y muerte entre los nahuas del México central, siglo XVI, trans. y ed., Miguel León-Portilla y Sarah Cline, con la colaboración de Juan Carlos Torres López (Ciudad de México: Universidad Iberoamericana, 2023), 42.