something that is made and grows up in the sea (see Molina)
Orthographic Variants:
uei apancayotl
Alonso de Molina:
uei apancayotl. cosa que se cria y se haze enla mar. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 155v. col. 1. Thanks to Joe Campbell for providing the transcription.