hardening

definition: the act of making something harder (firmer or tighter or more compact)
example:
speech part: noun
synonyms:
definition: the process of becoming hard or solid by cooling or drying or crystallization
example: the hardening of concrete
speech part: noun
synonyms: set solidifying solidification curing
definition: abnormal hardening or thickening of tissue
example:
speech part: noun
synonyms:

How hardening is being used?