The action of impair, v.; making worse, deterioration, impairment.

The action of fail, v., in various senses; an instance of this, a failure. †for, without (any) failing = for, without fail (see fail, n.1).

The action of making something more serious, aggravation. (See aggrieve, v. 2.) Obsolete.

The action of decay, v.

The action of fade, v.1; (also) the period of decay. fading out: a gradual dying out.

Deterioration.

figurative. The fact or process of deteriorating or becoming impaired, esp. through inactivity or lack of use.

The process of degenerating or becoming degenerate; the falling off from ancestral or earlier excellence; declining to a lower or worse stage of…

In negative sense: an increase or intensification of something undesirable. Obsolete.

deterioration, decline.

Increase of gravity or seriousness; aggravation.

The action of disimproving; the reverse of improvement; a change for the worse.

The act or process of diminishing in strength, vigour, etc.; decline; deterioration.

The action or process of deteriorating, a growing or making worse; a deteriorated condition.

Chiefly formal. Worsening, deterioration; (sometimes) spec. depreciation, disapproval, criticism; an instance of this; a depreciatory or critical…

Aggravation of a condition, etc.; also concrete.

In extended use: a state of decline, degeneration, atrophy, etc.

gen. Deterioration, reduction, falling away; an instance of this.

(un-, prefix1 affix 6.)

The process or fact of becoming worse; an instance of this.

= worsening, n.