obdurate
[L. obduro, to harden; ob and duro.]
a2.
obdurate
Hardened in heart; inflexibly hard; persisting obstinately in sin or impenitence.
obdurate
Hardened against good or favor; stubborn; unyielding; inflexible. The custom of evil makes the heart obdurate against whatsoever instructions to the contrary.
obdurate
Harsh; rugged; as an obdurate consonant.
obdurate
To harden.