alum

5 ENTRIES FOUND:

al·um

noun \ˈal-əm\

Definition of ALUM

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 alum b : one consisting of an ammonium aluminum sulfate NH4Al(SO4)2·12H2O—called also ammonia alum, ammonium alum
2
: any of various double salts isomorphous with potassium aluminum sulfate

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