to plate (with metal) or to veneer (with wood) a horseshoe (see Molina)
IPAspelling:
kɑkɑpɑːntiw
Alonso de Molina:
cacapantiuh. ni. (pret. onicacapantia.) chapear la herradura dela bestia. Alonso de Molina, Vocabulario en lengua castellana y mexicana y mexicana y castellana, 1571, part 2, Nahuatl to Spanish, f. 10v. col. 1. Thanks to Joe Campbell for providing the transcription.