The Collaborative International Dictionary of English v.0.48:

Growth \Growth\ (gr[=o]th), n. [Icel. gr[=o][eth]r,
   gr[=o][eth]i. See Grow.]
   1. The process of growing; the gradual increase of an animal
      or a vegetable body; the development from a seed, germ, or
      root, to full size or maturity; increase in size, number,
      frequency, strength, etc.; augmentation; advancement;
      production; prevalence or influence; as, the growth of
      trade; the growth of power; the growth of intemperance.
      Idle weeds are fast in growth. --Shak.
      [1913 Webster]

   2. That which has grown or is growing; anything produced;
      product; consequence; effect; result.
      [1913 Webster]

            Nature multiplies her fertile growth. --Milton.
      [1913 Webster]

WordNet (r) 3.0 (2006):

growth
    n 1: (biology) the process of an individual organism growing
         organically; a purely biological unfolding of events
         involved in an organism changing gradually from a simple to
         a more complex level; "he proposed an indicator of osseous
         development in children" [syn: growth, growing,
         maturation, development, ontogeny, ontogenesis]
         [ant: nondevelopment]
    2: a progression from simpler to more complex forms; "the growth
       of culture"
    3: a process of becoming larger or longer or more numerous or
       more important; "the increase in unemployment"; "the growth
       of population" [syn: increase, increment, growth] [ant:
       decrease, decrement]
    4: vegetation that has grown; "a growth of trees"; "the only
       growth was some salt grass"
    5: the gradual beginning or coming forth; "figurines presage the
       emergence of sculpture in Greece" [syn: emergence,
       outgrowth, growth]
    6: (pathology) an abnormal proliferation of tissue (as in a
       tumor)
    7: something grown or growing; "a growth of hair"

Moby Thesaurus II by Grady Ward, 1.0:

243 Moby Thesaurus words for "growth":
   about-face, abscess, access, accession, accomplishment, accretion,
   accrual, accruement, accumulation, addition, advance, advancement,
   aggrandizement, ague, alchemy, amplification, anemia, ankylosis,
   anoxia, apnea, appreciation, ascent, asphyxiation, assimilation,
   assumption, asthma, ataxia, atrophy, augmentation, backache,
   ballooning, becoming, benign tumor, bleeding, blennorhea, bloating,
   blossoming, boom, boost, bottoming out, broadening, budding,
   buildup, burgeoning, business cycle, business fluctuations, bust,
   cachexia, cachexy, callosity, callus, cancer, carcinoma, change,
   change-over, chill, chills, clump, colic, constipation, conversion,
   convulsion, cooling off, corn, coughing, crescendo, crisis, crop,
   cultivation, cyanosis, cyst, depression, development,
   developmental change, diarrhea, dizziness, downturn, dropsy,
   dysentery, dyspepsia, dyspnea, economic cycle, economic expansion,
   economic growth, edema, elaboration, elevation, emaciation,
   enlargement, evolution, evolutionary change, evolvement, evolving,
   excrescence, expanding economy, expansion, explication, extension,
   fainting, fatigue, fever, fibrillation, flip-flop, flood,
   flowering, flux, fungosity, fungus, furtherance, gain, gemmation,
   germination, gradual change, greatening, gush, hassock, hemorrhage,
   high blood pressure, high growth rate, hike, hydrops, hypertension,
   hypotension, icterus, improvement, increase, increment,
   indigestion, inflammation, inflation, insomnia, intumescence,
   itching, jaundice, jump, labored breathing, lapse, leap, low,
   low blood pressure, lumbago, lump, luxuriation, malignant growth,
   marasmus, market expansion, maturation, metastatic tumor, mole,
   morbid growth, mounting, multiplication, nasal discharge,
   natural development, natural growth, naturalization, nausea,
   necrosis, neoplasm, nevus, nonmalignant tumor, nonviolent change,
   nurturing, outgrowth, overgrowth, pain, paralysis, passage, peak,
   peaking, plantation, planting, procreation, productiveness,
   progress, progression, proliferation, prosperity, proud flesh,
   pruritus, pullulation, raise, rash, re-formation, recession,
   reconversion, recovery, reduction, reproduction, resolution,
   reversal, rheum, ripening, rise, sarcoma, sclerosis, seizure,
   shift, shock, skin eruption, slowdown, slump, sneezing,
   snowballing, sore, spasm, spread, sprouting, stand, success, surge,
   swelling, switch, switch-over, tabes, tachycardia, transformation,
   transit, transition, tuft, tumescence, tumor, turning into,
   tussock, unfolding, up, upgrowth, upping, upset stomach, upsurge,
   upswing, uptrend, upturn, vegetation, verruca, vertigo, volte-face,
   vomiting, wart, wasting, waxing, wen, widening