The Collaborative International Dictionary of English v.0.48:

Preparation \Prep`a*ra"tion\, n. [F. pr['e]paration, L.
   praeparatio. See Prepare.]
   [1913 Webster]
   1. The act of preparing or fitting beforehand for a
      particular purpose, use, service, or condition; previous
      arrangement or adaptation; a making ready; as, the
      preparation of land for a crop of wheat; the preparation
      of troops for a campaign.
      [1913 Webster]

   2. The state of being prepared or made ready; preparedness;
      readiness; fitness; as, a nation in good preparation for
      war.
      [1913 Webster]

   3. That which makes ready, prepares the way, or introduces; a
      preparatory act or measure.
      [1913 Webster]

            I will show what preparations there were in nature
            for this dissolution.                 --T. Burnet.
      [1913 Webster]

   4. That which is prepared, made, or compounded by a certain
      process or for a particular purpose; a combination.
      Specifically:
      (a) Any medicinal substance fitted for use.
      (b) Anything treated for preservation or examination as a
          specimen.
      (c) Something prepared for use in cookery.
          [1913 Webster]

                I wish the chemists had been more sparing who
                magnify their preparations.       --Sir T.
                                                  Browne.
          [1913 Webster]

                In the preparations of cookery, the most
                volatile parts of vegetables are destroyed.
                                                  --Arbuthnot.
          [1913 Webster]

   5. An army or fleet. [Obs.] --Shak.
      [1913 Webster]

   6. (Mus.) The holding over of a note from one chord into the
      next chord, where it forms a temporary discord, until
      resolved in the chord that follows; the anticipation of a
      discordant note in the preceding concord, so that the ear
      is prepared for the shock. See Suspension.
      [1913 Webster]

   7. Accomplishment; qualification. [Obs.] --Shak.
      [1913 Webster]

WordNet (r) 3.0 (2006):

preparation
    n 1: the activity of putting or setting in order in advance of
         some act or purpose; "preparations for the ceremony had
         begun" [syn: preparation, readying]
    2: a substance prepared according to a formula; "the physician
       prescribed a commercial preparation of the medicine" [syn:
       formulation, preparation]
    3: the cognitive process of thinking about what you will do in
       the event of something happening; "his planning for
       retirement was hindered by several uncertainties" [syn:
       planning, preparation, provision]
    4: the state of having been made ready or prepared for use or
       action (especially military action); "putting them in
       readiness"; "their preparation was more than adequate" [syn:
       readiness, preparedness, preparation]
    5: (music) a note that produces a dissonant chord is first heard
       in a consonant chord; "the resolution of one dissonance is
       often the preparation for another dissonance" [ant:
       resolution]
    6: activity leading to skilled behavior [syn: training,
       preparation, grooming]
    7: preparatory school work done outside school (especially at
       home) [syn: homework, prep, preparation]
    8: the act of preparing something (as food) by the application
       of heat; "cooking can be a great art"; "people are needed who
       have experience in cookery"; "he left the preparation of
       meals to his wife" [syn: cooking, cookery, preparation]

Moby Thesaurus II by Grady Ward, 1.0:

207 Moby Thesaurus words for "preparation":
   accouterment, adaptation, anticipation, apprenticeship,
   architecture, armament, arrangement, arrangements, assembly, balm,
   balsam, basic training, breaking, breeding, briefing, building,
   casting, catering, chandlery, composing, composition, compound,
   concoction, conditioning, construction, contemplation, conversion,
   crafting, craftsmanship, cramming, creation, cultivation,
   development, devising, discipline, discretion, drill, drilling,
   drops, drug, education, elaboration, electuary, elixir, endowment,
   envisagement, envisionment, equipment, erection, ethical drug,
   exercise, extraction, fabrication, farseeingness, farsightedness,
   fashioning, fetching-up, finding, fitness, fitting out, forecast,
   foreglance, foregleam, foreglimpse, forehandedness, foreseeing,
   foresight, foresightedness, formation, forming, formulation,
   fostering, foundation, framing, furnishing, furnishment,
   generic name, grooming, groundwork, growing, handicraft, handiwork,
   harmonization, harvesting, herbs, housebreaking, improvement,
   in-service training, inhalant, instruction, instrumentation,
   intonation, investment, lincture, linctus, logistics,
   longsightedness, looking ahead, machining, making, manual training,
   manufacture, manufacturing, materia medica, material, measures,
   medicament, medication, medicinal, medicinal herbs, medicine,
   military training, milling, mining, mixture, modulation, molding,
   nonprescription drug, nurture, nurturing, officinal,
   on-the-job training, orchestration, organization, organizing,
   outfitting, patent medicine, pharmacon, phrasing, physic, planning,
   plans, powder, practice, prediction, prefabrication, prep,
   preparing, prepping, prepublication, prescription drug, preview,
   prevision, proceedings, processing, procurement, producing,
   product, proprietary, proprietary medicine, proprietary name,
   prospect, prospection, providence, providing, provision,
   provisioning, provisions, prudence, purveyance, putting together,
   raising, readiness, readying, rearing, refining, rehearsal,
   reinforcement, replenishment, resolution, resupply, retailing,
   sagacity, selling, setting, shaping, simples, sloyd, smelting,
   solution, spadework, study, studying, stuff, subsidization,
   subsidy, substance, subvention, supply, supplying, suspension,
   swotting, syrup, teaching, theraputant, tisane, tone painting,
   training, transcription, tuition, upbringing, vegetable remedies,
   victualing, vocational education, vocational training, work,
   workmanship