Source : Webster's Revised Unabridged Dictionary (1913)

Excavate \Ex"ca*vate\, v. t. [imp. & p. p. {Excavated}; p. pr. &
   vb. n. {Excavating}.] [L. excavatus, p. p. of excavare to
   excavate; ex out + cavare to make hollow, cavus hollow. See
   {Cave}.]
   1. To hollow out; to form cavity or hole in; to make hollow
      by cutting, scooping, or digging; as, to excavate a ball;
      to excavate the earth.

   2. To form by hollowing; to shape, as a cavity, or anything
      that is hollow; as, to excavate a canoe, a cellar, a
      channel.

   3. (Engin.) To dig out and remove, as earth.

            The material excavated was usually sand. --E. L.
                                                  Corthell.

   {Excavating pump}, a kind of dredging apparatus for
      excavating under water, in which silt and loose material
      mixed with water are drawn up by a pump. --Knight.

Source : WordNet®

excavate
     v 1: lay bare through digging; "Schliemann excavated Troy" [syn:
          {unearth}]
     2: find by digging in the ground; "I dug up an old box in the
        garden" [syn: {dig up}, {turn up}]
     3: form by hollowing; "Carnegie had a lake excavated for
        Princeton University's rowing team"; "excavate a cavity"
     4: remove the inner part or the core of; "the mining company
        wants to excavate the hillsite" [syn: {dig}, {hollow}]