something ample, gross, fat, thick, or bulky, such as a cloth or the like (see Molina)
IPAspelling:
kopetik
Alonso de Molina:
copetic. cosa basta o grossera, como manta o cosa semejante. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 24v. col. 1. Thanks to Joe Campbell for providing the transcription.