hardened

Etymology

verb

1. simple past and past participle of harden

adj

1. Inured; toughened.
2. Unfeeling; pitiless; callous.
   The bloody scene could reduce even the most hardened soldier to tears.
   In the past, Lutao was considered somewhat mysterious, because of the national penitentiary which housed the most hardened criminals, and the restrictions on travel to the island, which have since been loosened. April 17, 1983, “Progress for Green Island”, in 自由中國週報 [Free China Weekly], volume XXIV, number 15, Taipei, →ISSN, →OCLC, page 2, column 3
   Hardened royalists staged a protest against Amnesty International Thailand at Silom Complex on Monday. The group said that the human rights watchdog is undermining the country’s stability by campaigning for the rights of the detained protest leaders who are calling for the reformation of the royal institution. 2021-11-29, Erich Parpart, “Ultra royalists condemn Amnesty International, call for their removal”, in Thai Enquirer, Thai Enquirer, retrieved 2021-11-29
3. Firmly established or unlikely to change; inveterate.
4. (computing, military) Having extra defences against attack; highly fortified.
   a hardened air base
   a hardened server