an act of improving or the state of being improved.

a change or addition by which a thing is improved.

a person or thing that represents an advance on another in excellence or achievement

The new landlord is a great improvement over his greedy predecessor.

a bringing into a more valuable or desirable condition, as of land or real property; betterment.

something done or added to real property that increases its value.

profitable use, as of a period of time.

noun

damage , decline , decrease , diminishing , harm , hurt , injury , weakening , worsening

noun

advance , advancement , amelioration , amendment , augmentation , betterment , change , civilization , correction , cultivation , development , elevation , enhancement , enrichment , furtherance , gain , growth , increase , preferment , progress , progression , promotion , rally , reclamation , recovery , rectification , reformation , regeneration , renovation , revision , rise , upbeat , upgrade , upswing , melioration