1

alum

noun al·um \ ˈa-ləm \

Definition of alum

1 : a potassium aluminum sulfate KAl(SO4)2·12H2O or an ammonium aluminum sulfate NH4Al(SO4)2·12H2O used especially for its astringent and styptic properties
2 : any of various double salts isomorphous with potassium aluminum sulfate

Origin and Etymology of alum

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

Other Chemical Engineering Terms


2

alum

noun \ ə-ˈləm \

Definition of alum

: alumnus, alumna
  • a Yale alum

Origin and Etymology of alum

by shortening

3

alum

abbreviation

Definition of alum

Other Chemical Engineering Terms


ALUM Defined for Kids

alum

noun al·um \ ˈa-ləm \

Definition of alum for Students

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

Medical Dictionary

alum

noun al·um \ ˈal-əm \

medical 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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