v. t. 1. To subject to a process which converts the surface of iron into steel. [ 1913 Webster ]

2. To render insensible to good influences. [ 1913 Webster ]

a. 1. Having the surface hardened, as iron tools. [ 1913 Webster ]

2. Hardened against, or insusceptible to, good influences; rendered callous by persistence in wrongdoing or resistance of good influences; -- said of persons. [ 1913 Webster ]

n. The act or process of converting the surface of iron into steel. Ure. [ 1913 Webster ]

☞ Casehardening is now commonly effected by cementation with charcoal or other carbonizing material, the depth and degree of hardening (carbonization) depending on the time during which the iron is exposed to the heat. See Cementation. [ 1913 Webster ]