nightcap

A nightcap is a type of soft, close-fitting hat worn in bed. Historically, nightcaps were common for both men and women, especially during colder months. Their primary purpose was to retain body heat and keep the head warm throughout the night. In earlier times, before central heating was widespread, this was a significant comfort.

Nightcaps were typically made from materials like linen, cotton, or wool. Designs varied, ranging from simple skullcap shapes to more elaborate styles with decorative tassels or ribbons. For some, wearing a nightcap also served to protect the hair from dust or the chill of an unheated room. In some cultures, the nightcap could also be a symbol of status or indicate a certain social standing.

While less common today due to modern bedding and heated homes, nightcaps are still occasionally worn by individuals seeking extra warmth or as a matter of personal habit. The term "nightcap" is also used metaphorically to refer to a final alcoholic drink consumed before going to bed, suggesting a relaxing end to the day, much like the literal garment provided comfort and warmth.