a punch tool, or an awl (a pointed instrument) (see Molina)
IPAspelling:
kojolomitɬ
Alonso de Molina:
coyolomitl. punzon, o alesna. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 24r. col. 1. Thanks to Joe Campbell for providing the transcription.