General deterioration:
* Degeneration: This is the most direct and literal option, referring to the process of becoming worse.
* Decline: This emphasizes a downward trend or a loss of quality.
* Decay: This emphasizes the gradual breaking down or disintegration.
Moral or ethical decline:
* Depravity: This refers to a state of moral corruption or wickedness.
* Corruption: This implies a loss of integrity or moral principles.
* Vice: This emphasizes a particular immoral habit or practice.
Social or cultural decline:
* Decadence: This suggests a decline in societal values and standards.
* Degradation: This emphasizes the lowering of social standing or moral character.
Specific contexts:
You might also use more specific terms like "dissolution" (for the breaking down of something), "degradation" (for a loss of quality or value), or "debasement" (for a lowering of moral or intellectual standards).
The best choice depends on the specific context and the nuance you want to convey.