The Collaborative International Dictionary of English v.0.48:

Thrive \Thrive\ (thr[imac]v), v. i. [imp. Throve (thr[=o]v) or
   Thrived (thr[imac]vd); p. p. Thrived or Thriven
   (thr[i^]v"'n); p. pr. & vb. n. Thriving.] [OE.
   [thorn]riven, Icel. [thorn]r[imac]fask; probably originally,
   to grasp for one's self, from [thorn]r[imac]fa to grasp; akin
   to Dan. trives to thrive, Sw. trifvas. Cf. Thrift.]
   1. To prosper by industry, economy, and good management of
      property; to increase in goods and estate; as, a farmer
      thrives by good husbandry.
      [1913 Webster]

            Diligence and humility is the way to thrive in the
            riches of the understanding, as well as in gold.
                                                  --I. Watts.
      [1913 Webster]

   2. To prosper in any business; to have increase or success.
      "They by vices thrive." --Sandys.
      [1913 Webster]

            O son, why sit we here, each other viewing
            Idly, while Satan, our great author, thrives?
                                                  --Milton.
      [1913 Webster]

            And so she throve and prospered.      --Tennyson.
      [1913 Webster]

   3. To increase in bulk or stature; to grow vigorously or
      luxuriantly, as a plant; to flourish; as, young cattle
      thrive in rich pastures; trees thrive in a good soil.
      [1913 Webster]

WordNet (r) 3.0 (2006):

thrive
    v 1: grow vigorously; "The deer population in this town is
         thriving"; "business is booming" [syn: boom, thrive,
         flourish, expand]
    2: make steady progress; be at the high point in one's career or
       reach a high point in historical significance or importance;
       "The new student is thriving" [syn: thrive, prosper, fly
       high, flourish]

Moby Thesaurus II by Grady Ward, 1.0:

54 Moby Thesaurus words for "thrive":
   advance, arrive, batten, be energetic, be vigorous, bloom, blossom,
   boom, brew, burgeon, burst with energy, come on, develop, fatten,
   flourish, flower, fructify, gather, germinate, go, grow, grow fat,
   grow up, have energy, hypertrophy, increase, make out, mature,
   mushroom, outgrow, overdevelop, overflow with energy, overgrow,
   overtop, procreate, progress, prosper, pullulate, reproduce, ripen,
   score, shoot up, spring up, sprout, sprout up, succeed, tower,
   turn out well, upshoot, upspear, upspring, upsprout, vegetate,
   wax