Menstruum

menstruum
    n 1: (archaic) a solvent
    2: the monthly discharge of blood from the uterus of nonpregnant
       women from puberty to menopause; "the women were sickly and
       subject to excessive menstruation"; "a woman does not take
       the gout unless her menses be stopped"--Hippocrates; "the
       semen begins to appear in males and to be emitted at the same
       time of life that the catamenia begin to flow in females"--
       Aristotle [syn: {menstruation}, {menses}, {menstruum},
       {catamenia}, {period}, {flow}]
    

Menstruum \Men"stru*um\, n.; pl. E. {Menstruums}, L. {Menstrua}.
   [L. menstruus. See {Menstruous}.]
   Any substance which dissolves a solid body; a solvent.
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         The proper menstruum to dissolve metal.  --Bacon.
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         All liquors are called menstruums which are used as
         dissolvents, or to extract the virtues of ingredients
         by infusion or decoction.                --Quincy.
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   Note: The use is supposed to have originated in some notion
         of the old chemists about the influence of the moon in
         the preparation of dissolvents. --Johnson.
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