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Synonyms

nocturnal

American  
[nok-tur-nl] / nɒkˈtɜr nl /

adjective

  1. of or relating to the night (diurnal ).

  2. done, occurring, or coming at night.

    nocturnal visit.
    Synonyms:
    nighttime

  3. active at night (diurnal ).

    nocturnal animals.

  4. opening by night and closing by day, as certain flowers (diurnal ).

noun

  1. Archaic. an astrolabe for telling time at night or for determining latitude by the position of certain stars in reference to Polaris.

nocturnal British  
/ nɒkˈtɜːnəl /

adjective

  1. of, used during, occurring in, or relating to the night

  2. (of animals) active at night

  3. (of plants) having flowers that open at night and close by day

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
nocturnal Scientific  
/ nŏk-tûr′nəl /

  1. Occurring at night.

  2. Most active at night. Many animals, such as owls and bats, are nocturnal.

  3. Having flowers that open during the night and close at daylight. Nocturnal plants are often pollinated by moths.

  4. Compare diurnal

Other Word Forms

  • nocturnality noun
  • nocturnally adverb
  • nonnocturnal adjective
  • nonnocturnally adverb
  • seminocturnal adjective
  • unnocturnal adjective
  • unnocturnally adverb

Etymology

Origin of nocturnal

From the Late Latin word nocturnālis, dating back to 1475–85. See nocturn, -al 1

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

In person, she has a newfound ease and confidence that suggests her nocturnal odysseys paid off.

From BBC • Apr. 2, 2026

It follows 55-year-old Palestinian cab driver Hassan, played with warmth and subtlety by Ehab Salami, as he ferries passengers through the nocturnal streets of Berlin.

From Barron's • Feb. 21, 2026

Mr. Scorsese makes his nocturnal vision pop with every glowing streetlight and every thick raindrop.

From The Wall Street Journal • Feb. 6, 2026

I would wake earlier, but I think in a past life I was a two-toed sloth or something because I’m nocturnal and I move very slowly.

From Los Angeles Times • Dec. 12, 2025

Even the nocturnal creatures crawled out from their burrows, into daylight, to join the celebration.

From "The Wild Robot Escapes" by Peter Brown

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.