diurnal

adjective di·ur·nal \ dī-ˈər-nᵊl \

|Updated on: 1 Jul 2018

Examples: diurnal in a Sentence

1 a : recurring every day

diurnal tasks

b : having a daily cycle

diurnal tides

2 a : of, relating to, or occurring in the daytime

the city's diurnal noises

b biology : active chiefly in the daytime

diurnal animals

c botany : opening during the day and closing at night

diurnal flowers

—

diurnally

play \-nᵊl-ē\ adverb

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Examples of diurnal in a Sentence

a love as constant and certain as the diurnal tides

Recent Examples of diurnal from the Web

That leaves her beachside club almost the entire day to entertain the diurnal, even if that’s the only trait some of her patrons have in common.

— New York Times, "You Can’t Hurt Lindsay Lohan Now," 26 June 2018
Sun bears, for example, are typically diurnal and sun-loving creatures; in undisturbed areas less than 20% of their activity occurred at night.

— kaitlyn gaynor, CNN, "To avoid humans, more wildlife now work the night shift," 14 June 2018
That’s the conclusion of a new study, which shows that a variety of previously diurnal animals such as foxes, deer, and boars have become nocturnal to avoid human activity out of fear.

— elizabeth gamillo, Science | AAAS, "Human activity is causing more and more animals to embrace the night," 14 June 2018
Circadian lighting aims to keep the body’s internal clock aligned with the 24-hour diurnal/nocturnal cycle by emitting bright bluish light during the day to suppress the melatonin that our brains produce as a natural sleep aid.

— New York Times, "These Lights Are Like a Mood Ring for Your Room," 8 May 2018
Eighty mile-per-hour winds blowing from the Pacific, coupled with a large diurnal temperature swing, cause vines to struggle, which may make for difficult farming but ultimately concentrates the fruit.

— bryce wiatrak, San Francisco Chronicle, "Community of small growers emerges on Cupertino’s Montebello Road," 28 Feb. 2018
The official Coachella Day Club has brought the diurnal ruckus to nearby Palm Springs with top-notch electronic music talent since 2014.

— kat bein, Billboard, "ODESZA, AC Slater, Illenium & More Announced for Coachella Day Club 2018," 26 Feb. 2018
Most moths are nocturnal; butterflies are essentially moths that have evolved to be diurnal, or active during the day, says Robert Robbins, a curator of lepidoptera at the National Museum of Natural History.

— anna diamond, Smithsonian, "What’s the Difference Between Moths and Butterflies and More Questions From Our Readers," 19 Apr. 2018
But humans are a diurnal species, meant to be active during the light phase and sleeping after dark, social calendars be damned.

— diane stoprya, The Cut, "Keeping the Romance Alive Is Tough When You Love Early Bedtimes," 6 Feb. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'diurnal.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.