(1):
(n.) The act of making profitable use or applicaton of anything, or the state of being profitably employed; a turning to good account; practical application, as of a doctrine, principle, or theory, stated in a discourse.
(2):
(n.) A useful addition to, or modification of, a machine, manufacture, or composition.
(3):
(n.) The act of improving; advancement or growth; promotion in desirable qualities; progress toward what is better; melioration; as, the improvement of the mind, of land, roads, etc.
(4):
(n.) Valuable additions or betterments, as buildings, clearings, drains, fences, etc., on premises.
(5):
(n.) The state of being improved; betterment; advance; also, that which is improved; as, the new edition is an improvement on the old.
(6):
(n.) Increase; growth; progress; advance.