Principal English Translation:
to do something exclusively (see Carochi); to be single-minded, preoccupied with one's own affairs (see Karttunen); to just have one thing [to do] (see Molina)
Alonso de Molina:
ixcauia. niqu. (pret. oniquixcaui.) no tener mas de vna cosa.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 44v. col. 2. Thanks to Joe Campbell for providing the transcription.
ixcauia. nin. (pret. oninixcaui.) hazer algo asolas, o entender solamente enlo que me toca.
ixcauia. nicn. (pret. onicnixcaui.) comermelo yo todo o aprovecharse el solo de alguna cosa, sin partirla con otros.
ixcauia. nitla. (pret. onitlaixcaui.) entender en sola vna sola cosa.
Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 44v. col. 2. Thanks to Joe Campbell for providing the transcription.
Frances Karttunen:
IXCAHUIĀ vrefl, vt to be single-minded, preoccupied with one’s own affairs; to have or do just one thing to the exclusion of others / hacer algo a solas o entender solamante lo que me toca (M), no tener más de una cosa (M), comérmelo yo todo (M), aprovecharse él solo de alguna cosa, sin partirla con otros (M), entender en sola una sola cosa (M) [(r)Cf.111V]. It is possible that C fails to mark a long initial vowel and that this is derived from ĪX-TLI and CĀHU(A).
Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 111.
Horacio Carochi / English:
ixcahuia = to do something exclusively
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), 504, and see 407 (n5)
Attestations from sources in English:
çan oquixcavhya y tequipa nemi mopapatla y ce oya tequipa y cequiti comotemolia y quimoqualtia ça mocepatlayecoltia = All they do is take turns going on tribute labor. One went on tribute labor; some are looking for a way to get fed. They just all try to make a living together. (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), 208–209.
Attestations from sources in Spanish:
auh zan conixcahuique yniquinmatica oquichiuh[que] in calli = y entre ambos labraron y edificaron las casas (Ciudad de Mexico, 1578)
Luis Reyes García, Eustaquio Celestino Solís, Armando Valencia Ríos, et al, Documentos nauas de la Ciudad de México del siglo XVI (México: Centro de Investigación y Estudios Superiores en Antropología Social y Archivo General de la Nación, 1996), 149.
maxitechmoquaxochtilli maxitechtepantica maceccan tiyecan matoconixcauican yn tleyn toconnequiltiz = Ustedes pongan nuestros linderos, que estemos separados; sea aparte para nosotros lo que tú desees. (Quauhtinchan, s. XVI)
Historia Tolteca-Chichimeca, eds. Paul Kirchhoff, Lina Odena Güemes, y Luis Reyes García (México: CISINAH, INAH-SEP, 1976), 222.