sundown

sun +‎ down

sundown (countable and uncountable, plural sundowns)

1. (US) Sunset.

   We'll meet by the pier at sundown.

2. (countable) A hat with a wide brim to shade the eyes from sunlight.

• dusk

sundown (third-person singular simple present sundowns, present participle sundowning, simple past and past participle sundowned)

1. (intransitive) to experience an episode or an onset of some detrimental mental condition like agitation, anxiety, hallucination or dementia, daily at nightfall.
   • 2009, Kay Cameron, ‎Tim Rhodus, Life With God 101

     "She also “sundowned”, and someone had to keep an eye on her 24-7."

• sundowner
• sundowning