temper

Temper your language around children.

Tempering is a heat treatment technique applied to metals, alloys, and glass to achieve greater toughness by increasing the strength of materials and/or ductility. Tempering is performed by a controlled reheating of the work piece to a temperature below its lower eutectic critical temperature.

With which the damned ghosts he governeth, / And furies rules, and Tartare tempereth.

You fools! I and my fellows

Are ministers of fate: the elements

Of whom your swords are temper'd may as well

Wound the loud winds, or with bemock'd-at stabs

Kill the still-closing waters, as diminish

One dowle that's in my plume; […]

Puritan austerity was so tempered by Dutch indifference, that mercy itself could not have dictated a milder system.

Thy sustenance […] serving to the appetite of the eater, tempered itself to every man's liking.