To make worse; to make inferior in quality or value; to impair; as, to deteriorate the mind.
- To diminish or impair in quality, character, or value: Time and neglect had deteriorated the property.
- To grow worse; degenerate: The weather deteriorated overnight. His health had deteriorated while he was in prison.
- To weaken or disintegrate; decay: The nation's highways are deteriorating at a rapid pace.