Vinegar plant

Vinegar \Vin"e*gar\, n. [OE. vinegre, F. vinaigre; vin wine (L.
   vinum) + aigre sour. See {Wine}, and {Eager}, a.]
   1. A sour liquid used as a condiment, or as a preservative,
      and obtained by the spontaneous (acetous) fermentation, or
      by the artificial oxidation, of wine, cider, beer, or the
      like.
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   Note: The characteristic sourness of vinegar is due to acetic
         acid, of which it contains from three to five per cent.
         Wine vinegar contains also tartaric acid, citric acid,
         etc.
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   2. Hence, anything sour; -- used also metaphorically.
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            Here's the challenge: . . . I warrant there's
            vinegar and pepper in't.              --Shak.
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   {Aromatic vinegar}, strong acetic acid highly flavored with
      aromatic substances.

   {Mother of vinegar}. See 4th {Mother}.

   {Radical vinegar}, acetic acid.

   {Thieves' vinegar}. See under {Thief}.

   {Vinegar eel} (Zool.), a minute nematode worm ({Leptodera
      oxophila}, or {Anguillula acetiglutinis}), commonly found
      in great numbers in vinegar, sour paste, and other
      fermenting vegetable substances; -- called also {vinegar
      worm}.

   {Vinegar lamp} (Chem.), a fanciful name of an apparatus
      designed to oxidize alcohol to acetic acid by means of
      platinum.

   {Vinegar plant}. See 4th {Mother}.

   {Vinegar tree} (Bot.), the stag-horn sumac ({Rhus typhina}),
      whose acid berries have been used to intensify the
      sourness of vinegar.

   {Wood vinegar}. See under {Wood}.
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