biphasic sleep

noun

The practice of sleeping twice per night, interrupted by a period of wakefulness; common in the days before electric lighting during the season with longer night.

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Meanings

nounbiphasic sleep (uncountable)
  1. uncountableThe practice of sleeping twice per night, interrupted by a period of wakefulness; common in the days before electric lighting during the season with longer night.

    Beginning in the 1700s, the industrial revolution—its light, its caffeine, its clocks, and above all, its work schedules—took Europe’s biphasic sleep in its hairy arms and mushed the two phases together.

    2022 January 27, Derek Thompson, “Can Medieval Sleeping Habits Fix America’s Insomnia?”, in The Atlantic
  2. uncountableThe practice of taking a regular nap during the afternoon and sleeping fewer hours at night.
Cite this entry
APA

biphasic sleep. (n.d.). In WatkinsX Dictionary. Retrieved November 4, 2026, from https://dictionary.watkinsx.com/word/biphasic%20sleep

MLA

“biphasic sleep.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/biphasic%20sleep. Accessed November 4, 2026.

Chicago

WatkinsX Dictionary, s.v. “biphasic sleep,” accessed November 4, 2026, https://dictionary.watkinsx.com/word/biphasic%20sleep.

Source: biphasic sleep on Wiktionary, CC BY-SA 4.0.