The Collaborative International Dictionary of English v.0.48:

Grown \Grown\,
   p. p. of Grow.
   [1913 Webster]

WordNet (r) 3.0 (2006):

grown
    adj 1: (of animals) fully developed; "an adult animal"; "a grown
           woman" [syn: adult, big, full-grown, fully grown,
           grown, grownup]

Moby Thesaurus II by Grady Ward, 1.0:

87 Moby Thesaurus words for "grown":
   adult, assembled, big, blooming, blossoming, brought about,
   budding, built, burgeoning, cast, caused, constructed, crafted,
   created, crescent, custom, custom-built, custom-made, developed,
   done, effectuated, executed, extracted, fabricated, fashioned,
   florescent, flourishing, flowering, forged, formed, full-blown,
   full-fledged, full-grown, fully developed, gathered, growing,
   grown-up, handcrafted, handmade, harvested, homemade, homespun,
   hypertrophied, machine-made, machined, made, made to order,
   man-made, manufactured, marriable, marriageable, mass-produced,
   mature, matured, maturescent, milled, mined, molded, nubile,
   of age, of marriageable age, old, overdeveloped, overgrown,
   performed, prefab, prefabricated, processed, produced,
   put together, raised, rank, ready-for-wear, ready-formed,
   ready-made, ready-prepared, ready-to-wear, refined, ripe, ripened,
   shaped, smelted, sprouting, thriving, well-built, well-constructed,
   well-made