[1] : The Collaborative International Dictionary of English v.0.48

alum \al"um\, n. oe. alum, alom, of. alum, f. alun, fr. l.
   alumen alum. chem.
   a double sulphate formed of aluminium and some other element
   esp. an alkali metal or of aluminium. it has twenty-four
   molecules of water of crystallization.
   1913 webster

   note: common alum is the double sulphate of aluminium and
         potassium. it is white, transparent, very astringent,
         and crystallizes easily in octahedrons. the term is
         extended so as to include other double sulphates
         similar to alum in formula.
         1913 webster

[2] : The Collaborative International Dictionary of English v.0.48

alum \al"um\, v. t.
   to steep in, or otherwise impregnate with, a solution of
   alum; to treat with alum. --ure.
   1913 webster

[3] : WordNet (r) 2.0

alum
     n 1: a white crystalline double sulfate of aluminum: the ammonium
          double sulfate of aluminum syn: ammonia alum, ammonium
          alum
     2: a white crystalline double sulfate of aluminum: the
        potassium double sulfate of aluminum syn: potassium alum,
         potash alum
     3: a person who has received a degree from a school high
        school or college or university syn: alumnus, alumna,
         graduate, grad
     4: a double sulphate of aluminum and potassium that is used as
        an astringent among other things
see also:
ammonia alum ammonium alum potassium alum potash alum alumnus alumna 
graduate grad 

Alum >> A Words
Alum, definition of term: Alum
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