The worst company in Verona, Excellency—the most brazen, the most case-hardened.
Her experience of the previous year had made her case-hardened.
I thought I was case-hardened, but just tell me that you loved me then!
I have been so much buffeted about in war and by sea that I am case-hardened, and this too may go with the rest.
We get "case-hardened" to trouble as the years ...