Oil of verbena

Verbena \Ver*be"na\, n. [L. See {Vervain}.] (Bot.)
   A genus of herbaceous plants of which several species are
   extensively cultivated for the great beauty of their flowers;
   vervain.
   [1913 Webster]

   Note: Verbena, or vervain, was used by the Greeks, the
         Romans, and the Druids, in their sacred rites.
         --Brewer.
         [1913 Webster]

   {Essence of verbena}, {Oil of verbena}, a perfume prepared
      from the lemon verbena; also, a similar perfume properly
      called {grass oil}. See {Grass oil}, under {Grass}.

   {Lemon verbena}, or {Sweet verbena}, a shrubby verbenaceous
      plant ({Lippia citriodora}), with narrow leaves which
      exhale a pleasant, lemonlike fragrance when crushed.
      [1913 Webster]