The Collaborative International Dictionary of English v.0.48:

ground \ground\ (ground), v. t. [imp. & p. p. grounded; p. pr.
   & vb. n. grounding.]
   1. To lay, set, or run, on the ground.
      [1913 Webster]

   2. To found; to fix or set, as on a foundation, reason, or
      principle; to furnish a ground for; to fix firmly.
      [1913 Webster]

            Being rooted and grounded in love.    --Eph. iii.
                                                  17.
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            So far from warranting any inference to the
            existence of a God, would, on the contrary, ground
            even an argument to his negation.     --Sir W.
                                                  Hamilton
      [1913 Webster]

   3. To instruct in elements or first principles.
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   4. (Elec.) To connect with the ground so as to make the earth
      a part of an electrical circuit.
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   5. (Fine Arts) To cover with a ground, as a copper plate for
      etching (see Ground, n., 5); or as paper or other
      materials with a uniform tint as a preparation for
      ornament.
      [1913 Webster]

   6. To forbid (a pilot) to fly an airplane; -- usually as a
      disciplinary measure, or for reasons of ill health
      sufficient to interfere with performance.
      [PJC]

   7. To forbid (aircraft) to fly; -- usually due to the unsafe
      condition of the aircraft or lack of conformity to safety
      regulations; as, the discovery of a crack in the wing of a
      Trijet caused the whole fleeet to be grounded for
      inspection.
      [PJC]

   8. To temporarily restrict the activities of (a child),
      especially social activity outside the house; -- usually
      for bad or unsatisfactory conduct; as, Johnny was grounded
      for fighting at school and can't go to the movies for two
      weeks.
      [PJC]

The Collaborative International Dictionary of English v.0.48:

Grounding \Ground"ing\, n.
   1. The act, method, or process of laying a groundwork or
      foundation.
      [1913 Webster]

   2. Hence: [Nominalized form of ground[3], v. t.] Elementary
      instruction; instruction in the basic concepts of a topic
      or skill.
      [PJC]

   3. The act or process of applying a ground, as of color, to
      wall paper, cotton cloth, etc.; a basis.
      [1913 Webster]

WordNet (r) 3.0 (2006):

grounding
    n 1: education or instruction in the fundamentals of a field of
         knowledge; "he lacks the foundation necessary for advanced
         study"; "a good grounding in mathematics" [syn:
         foundation, grounding]
    2: fastening electrical equipment to earth [syn: grounding,
       earthing]