tencolli.

Headword: 
tencolli.
Principal English Translation: 

a type of chin strap worn by brave warriors to show their courage

Gran Diccionario Náhuatl, citing Wimmer (2004), "sorte de têntetl ou mentonnière que portaient les braves," https://gdn.iib.unam.mx/diccionario/tencolli; translated here to English by Stephanie Wood.