Definition of "sundowning" []

• A state of agitation, confusion, or delirium, especially in patients suffering from Alzheimer's disease, which begins daily at nightfall and which is alleviated by daylight. (noun)

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• "My doctor husband listens carefully to what he calls sundowning rants just in case there's any validity to the charges."
• "Light is especially important in the late afternoon and early evening, when a phenomenon known as sundowning kicks in."
• "The latter, called "sundowning," occurs in people with dementia, although the cause is unclear."