The Collaborative International Dictionary of English v.0.48:
improved \improved\ adj. 1. advanced to a more desirable or valuable or excellent state. Opposite of unimproved. [Narrower terms: built, reinforced; cleared, tilled ; {developed; grade ; {graded, graveled ] Also See: {restored. [WordNet 1.5] 2. changed for the better; as, her improved behavior. Syn: amended. [WordNet 1.5]