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1

alum

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noun al·um \ˈa-ləm\

Definition of alum

  1. 1 :  a potassium aluminum sulfate KAl(SO4)2·12H2O or an ammonium aluminum sulfate NH4Al(SO4)2·12H2O used especially as an emetic and as an astringent and styptic

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

  3. 3 :  aluminum sulfate



Origin of alum

Middle English, from Anglo-French alum, alun, from Latin alumen


First Known Use: 14th century

Other Chemical Engineering Terms


2

alum

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noun al·um \ə-ˈləm\

Definition of alum



Origin of alum

by shortening


First Known Use: 1910


3

alum

abbreviation al·um

Definition of alum



Other Chemical Engineering Terms


ALUM Defined for Kids

alum

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noun al·um \ˈa-ləm\

Definition of alum for Students

  1. :  either of two aluminum compounds that are used especially in medicine (as to stop bleeding)




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 b:  one consisting of an ammonium aluminum sulfate NH4Al(SO4)2·12H2O—called also ,

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




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