Verbs

(v)callous, cauterize, cauterisemake insensitive or callous; deaden feelings or morals

Adjectives

(s)callous, indurate, pachydermatousemotionally hardened“a callous indifference to suffering”, “cold-blooded and indurate to public opinion”
(s)calloused, callous, thickenedhaving calluses; having skin made tough and thick through wear“calloused skin”, “with a workman's callous hands”