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

Is it acceptable to use alum for alumnus or alumna?

The words that we have used to refer to people who have attended or graduated from a school, college, or university have changed a bit over the past several centuries. Traditionally, the word alumnus has been used to refer to a single male, whereas alumna has been used for a single woman. Initially the plural forms were alumni to refer to multiple men (or multiple men and women) and alumnae for multiple women. A little over a hundred years ago the shortened form of alum began to be used to describe a graduate or past attendee of either gender. Although many people feel that alum is informal, it is in increasing use, and we appear to be moving toward a greater acceptance of the word. The plural of alum is alums.

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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