sundowning

S1U1N1D2O1W4N1I1N1G2

noun

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.

Similar
nocturnal deliriumsundowner syndrome
Scrabble 15
Ask AI about this wordChatGPTClaudePerplexityGoogle AIGrok

Meanings

nounsundowning (uncountable)
  1. uncountablehuman sciencesA 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.

    1986, Norma Sullivan, Barry Fogel, “Could This Be Delirium?”, in The American Journal of Nursing, volume 86, number 12, page 1363
    1 more example

    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.

    2023 April 28, Abhijit Satpati, Thomas Neylan, Lea T. Grinberg, “Histaminergic neurotransmission in aging and Alzheimer's disease: A review of therapeutic opportunities and gaps”, in Alzheimer’s & Dementia: Translational Research & Clinical Interventions, volume 9, number 2, Wiley, →DOI, →ISSN

    Synonyms: nocturnal delirium, sundowner syndrome

verb
  1. gerundparticiplepresentpresent participle and gerund of sundown

Synonyms & antonyms

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

Similar
nocturnal deliriumsundowner syndrome
Also see
nocturnal deliriumsundowner syndrome

Origin

From sundown + -ing.

Full word history & related roots →

Translations

Chinese Mandarin 日落綜合徵 /日落综合征, 日落綜合症 /日落综合症
  • 日落綜合徵 /日落综合征nightly agitation, confusion, or delirium
  • 日落綜合症 /日落综合症nightly agitation, confusion, or delirium
  • 日落症候群nightly agitation, confusion, or delirium
Finnish auringonlaskuoireyhtymä
  • auringonlaskuoireyhtymänightly agitation, confusion, or delirium
Japanese 日暮れ時兆候
  • 日暮れ時兆候 (higure-doki chōkō)nightly agitation, confusion, or delirium
Polish zespół zachodzącego słońca
  • zespół zachodzącego słońcanightly agitation, confusion, or delirium
Cite this entry
APA

sundowning. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/sundowning

MLA

“sundowning.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/sundowning. Accessed November 3, 2026.

Chicago

WatkinsX Dictionary, s.v. “sundowning,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/sundowning.

Source: sundowning on Wiktionary, CC BY-SA 4.0.