ueimapilli. dedo pulgar dela mano. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 155v. col. 2. Thanks to Joe Campbell for providing the transcription.
Frances Karttunen:
HUĒIMAHPIL-LI thumb / dedo pulgar de la mano (M) [(2)Zp.103,158]. See HUĒ(I), MAHPIL-LI. Frances Karttunen, An Analytical Dictionary of Nahuatl (Norman: University of Oklahoma Press, 1992), 85.