noun
deterioration
dih-teer-ee-uh-RAY-shun/dɪˌtɪriəˈreɪʃn/
The process of becoming worse in condition, quality, or value.
The watering cans show progressive deterioration through increasingly severe corrosion.

Etymology
The underlying Latin verb expresses getting or making worse; deterioration names that process rather than merely a poor condition. The noun may have been formed in English or borrowed from French.
In context
the deterioration of Timber elements can result from rot fungal Decay bacteria Marine borers or insects
More examples
- Doctors monitor her closely for any deterioration in her health.
- Water damage causes rapid deterioration of the wooden beams.
- The report describes a steady deterioration in relations between the countries.
Forms
deterioration
deteriorate verb — To become worse in condition or quality.
Similar words
- decline
- Can describe decreasing quantity as well as worsening quality.
- decay
- Emphasizes gradual breakdown, especially through rotting or neglect.
- degradation
- Often emphasizes damage that reduces quality, usefulness, or integrity.