What is to destroy the active powers or essential qualities of; to change by chemical action. [Obs.] Chaucer. Quicksilver is mortified with turpentine. Bacon. He mortified pearls in vinegar. Hakewill called?

mortify — To destroy the active powers or essential qualities of; to change by chemical action. [Obs.] Chaucer. Quicksilver is mortified with turpentine. Bacon. He mortified pearls in vinegar. Hakewill. (Webster's 1913.)

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