hard ‧ ened /ˈhɑːdnd $ ˈhɑːr-/ BrE AmE adjective
[ Word Family: noun : ↑ hardship , ↑ hardness , ↑ hardiness ; adjective : ↑ hard , ↑ hardened , ↑ hardy ; adverb : ↑ hard , ↑ hardly ; verb : ↑ harden ]
1 . hardened criminal/police officer etc a criminal, police officer etc who has had a lot of experience of things that are shocking and is therefore less affected by them
2 . become hardened (to something) to become used to something shocking because you have seen it many times