the act or process of deteriorating.

the state or condition of having deteriorated.

a gradual decline, as in quality, serviceability, or vigor.

noun

betterment , building , construction , development , improvement

noun

abasement , adulteration , atrophy , corrosion , crumbling , debasement , decadence , decaying , declension , declination , decline , decomposition , degradation , degringolade , depreciation , descent , devaluation , dilapidation , disintegration , dislocation , disrepair , downfall , downgrade , downturn , drop , fall , lapse , lessening , perversion , retrogression , rotting , ruin , slump , spoiling , vitiation , worsening , degeneracy , degeneration , breakdown , putrefaction , putrescence , putridness , rot , rottenness , spoilage , corruption , labefaction , retrocession