eighteen ears of dried maize (or other countable food items) (see Molina)
Orthographic Variants:
caxtulolotl omei
Alonso de Molina:
caxtulolotl omei. deziocho mazorcas Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 13r. col. 2. Thanks to Joe Campbell for providing the transcription.