The Collaborative International Dictionary of English v.0.48:

full-grown \full-grown\ adj.
   1. .
      []

The Collaborative International Dictionary of English v.0.48:

Full-grown \Full"-grown`\, a.
   Having reached the limits of growth; mature; fully developed;
   -- used mostly of living organisms; as, A full-grown lion can
   easily kill an unarmed man.. "Full-grown wings." --Lowell.

   Syn: adult, big, fully grown, grown, grownup.[1913 Webster +
        WordNet 1.5]

WordNet (r) 3.0 (2006):

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