1. To extinguish; to overwhelm; to make an end of; said of flame and fire, of things burning, and figuratively of sensations and emotions; as, to quench flame; to quench a candle; to quench thirst, love, hate, etc. Ere our blood shall quench that fire. (Shak) The supposition of the lady’s death Will quench the wonder of her infamy. (Shak)
2. To cool suddenly, as heated steel, in tempering.
Synonym: To extinguish, still, stifle, allay, cool, check.
Origin: OE. Quenchen, AS. Cwencan in acwencan, to extinguish utterly, causative of cwincan, acwincan, to decrease, disappear; cf. AS. Cwinan, acwinan, to waste or dwindle away.