Dictionary.net

abnormal hardening or thickening of tissue

the act of making something harder (firmer or tighter or more compact)

abnormal hardening or thickening of tissue

the act of making something harder (firmer or tighter or more compact)

Making hard or harder.

That which hardens, as a material used for converting the surface of iron into steel.

Making hard or harder.

That which hardens, as a material used for converting the surface of iron into steel.

n. Act or process of making bodies more compact and impervious; especially, the tempering of iron or steel.