The Collaborative International Dictionary of English v.0.48:

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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The Collaborative International Dictionary of English v.0.48:

Aromatic \Ar`o*mat"ic\, Aromatical \Ar`o*mat"ic*al\, a. [L.
   aromaticus, Gr. ?: cf. F. aromatique. See Aroma.]
   Pertaining to, or containing, aroma; fragrant; spicy;
   strong-scented; odoriferous; as, aromatic balsam.
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   Aromatic compound (Chem.), one of a large class of organic
      substances, as the oils of bitter almonds, wintergreen,
      and turpentine, the balsams, camphors, etc., many of which
      have an aromatic odor. They include many of the most
      important of the carbon compounds and may all be derived
      from the benzene group, C6H6. The term is extended also
      to many of their derivatives.

   Aromatic vinegar. See under Vinegar.
      [1913 Webster]