The Collaborative International Dictionary of English v.0.48:

Basin \Ba"sin\, n. [OF. bacin, F. bassin, LL. bacchinus, fr.
   bacca a water vessel, fr. L. bacca berry, in allusion to the
   round shape; or perh. fr. Celtic. Cf. Bac.]
   [1913 Webster]
   1. A hollow vessel or dish, to hold water for washing, and
      for various other uses.
      [1913 Webster]

   2. The quantity contained in a basin.
      [1913 Webster]

   3. A hollow vessel, of various forms and materials, used in
      the arts or manufactures, as that used by glass grinders
      for forming concave glasses, by hatters for molding a hat
      into shape, etc.
      [1913 Webster]

   4. A hollow place containing water, as a pond, a dock for
      ships, a little bay. --Pope
      [1913 Webster]

   5. (Physical Geog.)
      (a) A circular or oval valley, or depression of the
          surface of the ground, the lowest part of which is
          generally occupied by a lake, or traversed by a river.
      (b) The entire tract of country drained by a river, or
          sloping towards a sea or lake.
          [1913 Webster]

   6. (Geol.) An isolated or circumscribed formation,
      particularly where the strata dip inward, on all sides,
      toward a center; -- especially applied to the coal
      formations, called coal basins or coal fields.
      [1913 Webster]