What is the meaning of indurate?

verb

• Become fixed or established.
  • usage: "indurated customs"
• Make hard or harder.
  • usage: "The cold hardened the butter"
  • synonyms: harden
• Become hard or harder.
  • usage: "The wax hardened"
  • synonyms: harden
• Cause to accept or become hardened to; habituate.
  • usage: "He was inured to the cold"
  • synonyms: inure, harden

adjective

• Emotionally hardened.
  • usage: "a callous indifference to suffering"; "cold-blooded and indurate to public opinion"
  • synonyms: callous, pachydermatous