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Medical Dictionary

alum

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noun al·um \ˈal-əm\

Medical Definition of alum

  1. 1:  either of two colorless or white crystalline double sulfates of aluminum used in medicine internally as emetics and locally as astringents and styptics:a:  one KAl(SO4)2·12H2O that is a sulfate of aluminum and potassium—called also potassium alumb:  one consisting of an ammonium aluminum sulfate NH4Al(SO4)2·12H2O—called also ammonia alum, ammonium alum

  2. 2:  any of various double salts isomorphous with potassium aluminum sulfate




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a division or portion of a pool or whole

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