Source : Webster's Revised Unabridged Dictionary (1913)

Asphalt \As"phalt\, Asphaltum \As*phal"tum\, n. [Gr. ?, of
   eastern origin: cf. F. asphalte.]
   1. Mineral pitch, Jews' pitch, or compact native bitumen. It
      is brittle, of a black or brown color and high luster on a
      surface of fracture; it melts and burns when heated,
      leaving no residue. It occurs on the surface and shores of
      the Dead Sea, which is therefore called Asphaltites, or
      the Asphaltic Lake. It is found also in many parts of
      Asia, Europe, and America. See {Bitumen}.

   2. A composition of bitumen, pitch, lime, and gravel, used
      for forming pavements, and as a water-proof cement for
      bridges, roofs, etc.; asphaltic cement. Artificial asphalt
      is prepared from coal tar, lime, sand, etc.

   {Asphalt stone}, {Asphalt rock}, a limestone found
      impregnated with asphalt.

Asphalt \As"phalt\, v. t.
   To cover with asphalt; as, to asphalt a roof; asphalted
   streets.

Source : WordNet®

asphalt
     n 1: mixed asphalt and crushed gravel or sand; used especially
          for paving but also for roofing
     2: a dark bituminous substance found in natural beds and as
        residue from petroleum distillation; consists mainly of
        hydrocarbons [syn: {mineral pitch}]
     v : cover with tar or asphalt; "asphalt the driveway"