资料来源 : pyDict

明矾

资料来源 : Webster's Revised Unabridged Dictionary (1913)

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.

   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.

Alum \Al"um\, v. t.
   To steep in, or otherwise impregnate with, a solution of
   alum; to treat with alum. --Ure.

资料来源 : WordNet®

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)