improvement

1. The act of improving; advancement or growth; a bettering
2. The act of making profitable use or application of anything, or the state of being profitably employed; practical application, for example of a doctrine, principle, or theory, stated in a discourse.
3. The state of being improved; betterment; advance
4. Something which is improved
5. Increase; growth; progress; advance.
6. Valuable additions or betterments, for example buildings, clearings, drains, fences, etc., on premises.
7. A useful addition to, or modification of, a machine, manufacture, or composition.