The Collaborative International Dictionary of English v.0.48:

Cultivate \Cul"ti*vate\ (k?l"t?-v?t), v. t. [imp. & p. p.
   Cultivated (-v?`t?d); p. pr. & vb. n. Cultivating
   (-v?`-t?ng).] [LL. cultivatus, p. p. of cultivare to
   cultivate, fr. cultivus cultivated, fr. L. cultus, p. p. of
   colere to till, cultivate. Cf. Colony.]
   1. To bestow attention, care, and labor upon, with a view to
      valuable returns; to till; to fertilize; as, to cultivate
      soil.
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   2. To direct special attention to; to devote time and thought
      to; to foster; to cherish.
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            Leisure . . . to cultivate general literature.
                                                  --Wordsworth.
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   3. To seek the society of; to court intimacy with.
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            I ever looked on Lord Keppel as one of the greatest
            and best men of his age; and I loved and cultivated
            him accordingly.                      --Burke.
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   4. To improve by labor, care, or study; to impart culture to;
      to civilize; to refine.
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            To cultivate the wild, licentious savage. --Addison.
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            The mind of man hath need to be prepared for piety
            and virtue; it must be cultivated to the end.
                                                  --Tillotson.
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   5. To raise or produce by tillage; to care for while growing;
      as, to cultivate corn or grass.
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WordNet (r) 3.0 (2006):

cultivate
    v 1: foster the growth of
    2: prepare for crops; "Work the soil"; "cultivate the land"
       [syn: cultivate, crop, work]
    3: teach or refine to be discriminative in taste or judgment;
       "Cultivate your musical taste"; "Train your tastebuds"; "She
       is well schooled in poetry" [syn: educate, school,
       train, cultivate, civilize, civilise]
    4: adapt (a wild plant or unclaimed land) to the environment;
       "domesticate oats"; "tame the soil" [syn: domesticate,
       cultivate, naturalize, naturalise, tame]

Moby Thesaurus II by Grady Ward, 1.0:

144 Moby Thesaurus words for "cultivate":
   advance, ameliorate, apprentice, approach, backset, beautify,
   better, break, break in, break the ice, breed, bring up,
   brown-nose, butter up, care for, carve, cherish, chisel, coddle,
   condition, convert, cosset, court, courteous, cradle, crop,
   cultivated, culture, cultured, cut, delve, develop, dig,
   discipline, distingue, dress, drill, dry-nurse, educate, elaborate,
   embellish, encourage, evolve, excite, exercise, extract, fallow,
   farm, feed, fertilize, fetch up, finish, fit, fondle, force, form,
   foster, further, groom, grow, harrow, harvest, hoe, house-train,
   housebreak, improve, instruct, labor, lavish care on,
   lick into shape, list, machine, make advances, make sensitive,
   make up to, manage, mature, mill, mine, mother, mulch, nourish,
   nurse, nurture, pamper, pay addresses to, pay court to, perfect,
   play up to, plow, polish, polished, polite, practice, prepare,
   process, produce, promote, propagate, prune, pump, put in tune,
   put to school, quicken, raise, rake, ready, rear, refine, refined,
   rehearse, ripen, run after, season, send to school, sensibilize,
   sensitize, sharpen, shine up to, smelt, spade, spoon-feed,
   stimulate, stir, suck up to, suckle, sustain, take in hand, teach,
   tend, thin, thin out, till, till the soil, train, urbane, weed,
   weed out, well-bred, wet-nurse, whet, woo, work, work on