What does "harden" mean?

Harden: To accustom by labor or suffering to endure with constancy; to strengthen; to stiffen; to inure; also, to confirm in wickedness or shame; to make unimpressionable. "Harden not your heart." Ps. xcv.

Additional senses

  1. 2.I would harden myself in sorrow. Job vi.
  2. 3.1. To become hard or harder; to acquire solidity, or more compactness; as, mortar hardens by drying. The deliberate judgment of those who knew him [A. Lincoln] has hardened into tradition. The Century.
  3. 4.To become confirmed or strengthened, in either a good or a bad sense. They, hardened more by what might most reclaim. Milton.

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