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.
   [1913 Webster]

   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]

WordNet (r) 3.0 (2006):

aromatic compound
    n 1: a hydrocarbon containing one or more benzene rings that are
         characteristic of the benzene series of compounds