hardened
/ˈhɑːdn̩d/
verb
Meaning
To become hard (tough, resistant to pressure).
To make something hard or harder (tough, resistant to pressure).
To strengthen.
To modify (a website or other system) to make it resistant to malicious attacks.
To become or make (a person or thing) resistant or less sensitive.
To become or make (a consonant) more fortis.
Synonyms
adjective
Meaning
Unfeeling or lacking emotion due to experience; callous.
"The bloody scene could reduce even the most hardened soldier to tears."
Firmly established or unlikely to change; inveterate.
Having extra defences against attack; highly fortified.
"a hardened air base"