to grow old or deteriorate physically with age

a medical condition in which an organ or system ceases to function properly

a period of temporary economic decline or contraction

to lose power, prosperity, or influence; to gradually deteriorate or go downhill

to decrease in strength, intensity, or amplitude, typically referring to signals, waves, or physical energy

the alternation between periods of prosperity and decline, typically in the context of a kingdom, dynasty, or organization

nervous exhaustion; neurasthenia; mental breakdown (often used to describe what is now understood to be clinical depression)

declining in strength, power, or vigor; becoming less effective or intense

to decline in prosperity, power, or status

(physics) half-life

to age prematurely; the state or process of premature senescence

the cycle of flourishing and then declining; fluctuations in prosperity or power

to decline and eventually die out or fall, especially in reference to civilizations, dynasties, or species

to gradually lose power, influence, or vitality; to wane

radioactive decay

long-lasting and not showing signs of decline or fading

a period of economic recession

to age prematurely

remaining strong and not weakening; unfailing or persistent over time

feeling uninspired, discouraged, or low in spirit and vigor

rotting, crumbling, or deteriorating physically or metaphorically

old and weak (idiom)

aged; decrepit

Weakening and close to total exhaustion; in terminal decline or on one's last legs.

economic recession

a psychological disorder characterized by obsessions, compulsions, phobias, or mental exhaustion, historically linked to obsessive-compulsive disorder

the transition or shift from a period of prosperity and success to one of decay or failure

national decline

decline in fortunes

to express pessimistic views about or predict the failure of something

an unpleasant, mean, or despicable person

to treat a debility according to its nature

decay curves

heat released as a result of radioactive decay