hardened

IPA: hˈɑrdʌnd

Having been accustomed or desensitized to something unpleasant through exposure or experience; inured.
Unfeeling; pitiless; callous.
Firmly established in a behavior seen as bad; unlikely to change one's ways; inveterate.
(computing, military) Having extra defences against attack; highly fortified.

Examples of "hardened" in Sentences

Playfair frowned and his expression hardened just a mite.
His expression hardened as he leaned over to unlace his boot.
He sniffed, and as Hap watched, his expression hardened once more.
Her expression hardened and she fixed the white cat with a cold stare.
Then her expression hardened and she strode after Fandral as if about to rush off to war.
His expression hardened when he spotted Adam, but just as quickly as his scowl appeared, it was replaced by a smile.