overharden

Etymology

From over- + harden.

overharden means to harden too much. Lexicurio rates it Sui generis — a strength score of 87 out of 100.

verb

To harden too much.“[I]t has acquir'd ſuch a hardneſs, that being throvvn againſt the floor it vvould rebound, and vvas brittle like over-harden'd Steel.”