a) 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.
"I look upon your city as the best place of improvement." -.
b) The act of making profitable use or application 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.
"Exercise is the chief source of improvement in all our faculties." -.
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