Definition of 'harden'

Verb

1. become hard or harder; "The wax hardened"
      Synonyms: indurate
      Antonyms: soften
2. make hard or harder; "The cold hardened the butter"
      Synonyms: indurate
      Antonyms: soften
3. harden by reheating and cooling in oil; "temper steel"
      Synonyms: temper
4. make fit; "This trip will season even the hardiest traveller"
      Synonyms: season
5. cause to accept or become hardened to; habituate; "He was inured to the cold"
      Synonyms: inure indurate

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