cueponaltia. nite. (pret. onitecueponalti.) hazer resplandecer a otro. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 26r. col. 2. Thanks to Joe Campbell for providing the transcription.
Frances Karttunen:
CUEPŌNALTIĀ caus. CUEPŌN(I) CUEPŌN(I) to shine, glow; for flowers to burts into bloom; for something to burts, explode / dar estallido el huevo o la castaña cuando lo asan, o abrirse y abrotar la flor o la rosa, o resplandecer alguna cosa (M) Nahuatl also has XŌTLA, which associates blooming with bursting into flame. Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 70.