sundowning

noun

1. (uncountable)A state of agitation, confusion, or delirium, especially in patients suffering from Alzheimer's disease, which begins each evening and which is alleviated by daylight.

   “Impaired judgment and sundowning (increased confusion when orienting cues diminish at night) often makes it necessary to restrict and protect the delirious patient.”

   “Polysomnography and othersleep measures show sleep fragmentation with shortening of N3 sleep togetherwith excessive daytime sleepiness (EDS) and sundowning as the main findings in AD patients.”

verb

1. (form-of, gerund, participle, present)present participle and gerund of sundown