Definition of "nocturnal" []

  • Of, relating to, or occurring in the night: nocturnal stillness. (adjective)
  • Botany Having flowers that open during the night. (adjective)
  • Zoology Most active at night: nocturnal animals. (adjective)
  • Of, used during, occurring in, or relating to the night (adjective)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

  • (of animals) active at night (adjective)
  • (of plants) having flowers that open at night and close by day (adjective) (c) HarperCollins Publishers Ltd 2016

Use "nocturnal" in a sentence
  • "She'd been researching what she called "nocturnal pressing spirit attacks," or what scientific literature called sleep paralysis."
  • "Neighbors ... said they wouldn't rest until the large black snake, which appears to be nocturnal, is no longer free."
  • "“The use of unguents and eye-powders and the dust of the road and the undesigned swallowing of saliva and the emission of seed in nocturnal pollution or at the sight of a strange woman and blooding and cupping; none of these things vitiates the fast.”"