What is the act or process of percolating, or filtering; filtration; straining. Specifically (Pharm.), the process of exhausting the virtues of a powdered drug by letting a liquid filter slowly through it called?

percolation — The act or process of percolating, or filtering; filtration; straining. Specifically (Pharm.), the process of exhausting the virtues of a powdered drug by letting a liquid filter slowly through it. (Webster's 1913.)

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