tempering (Adjective) — Moderating by making more temperate.
tempering (Noun) — Hardening something by heat treatment.
tempering (Verb) — Bring to a desired consistency, texture, or hardness by a process of gradually heating and cooling. ex. "temper glass"
tempering (Verb) — Harden by reheating and cooling in oil. ex. "temper steel"
tempering (Verb) — Adjust the pitch (of pianos).
tempering (Verb) — Make more temperate, acceptable, or suitable by adding something else; moderate. ex. "she tempered her criticism"
tempering (Verb) — Restrain.