Main entry: harden, indurate, inure
Definition: cause to accept or become hardened to; habituate
Usage: He was inured to the cold
Definition: make fit
Usage: This trip will season even the hardiest traveller
Definition: harden by reheating and cooling in oil
Usage: temper steel
Definition: become hard or harder
Usage: The wax hardened
Definition: make hard or harder
Usage: The cold hardened the butter