What does "vehicle" mean?

Vehicle: That which is used as the instrument of conveyance or communication; as, matter is the vehicle of energy. A simple style forms the best vehicle of thought to a popular assembly. Wirt.

Additional senses

  1. 2.(Pharm.) A substance in which medicine is taken.
  2. 3.(Paint.) Any liquid with which a pigment is applied, including whatever gum, wax, or glutinous or adhesive substance is combined with it. Note: Water is used in fresco and in water-color painting, the colors being consolidated with gum arabic; size is used in distemper painting. In oil painting, the fixed oils of linseed, nut, and poppy, are used; in encaustic, wax is the vehicle. Fairholt.

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