Callos (en. Calluses)

/ˈka.ʝos/

Slang Meanings

In some contexts, it refers to something tough or hard to break.
He is a tough man; he withstands any difficulty.
Es un hombre de callos; aguanta cualquier dificultad.
It is used to describe someone who is very stubborn.
There’s no way to convince him; he’s hard-headed.
No hay forma de convencerlo, tiene callos en la cabeza.