diurnal

adjective di·ur·nal \ dī-ˈər-nᵊl \

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

Sleepover camp options give festival goers a break from the commute and offers a ton of diurnal activities.

— kat bein, Billboard, "EDC Las Vegas Outlines Camping Plans for 2018," 9 Nov. 2017
The diurnal changes in blood pressure and heart rate are well known circadian rhythms.

— aimee swartz, The Cut, "How Your Body Keeps Time," 6 Oct. 2017
These zoologists know how to navigate the untamed land, accurately identify diurnal and nocturnal creatures and place covert camera traps to photograph the most elusive wildlife.

— kyle frischkorn, Smithsonian, "How Fly Guts Are Helping Researchers Catalog the Rainforest," 7 Aug. 2017
Crickets and frogs may jump start their evening chorus, diurnal animals might quiet down and even nocturnal animals like bats and owls might be lured into activity in the eclipse's totality.

— atlanta life, ajc, "How will your pets react to the solar eclipse?," 9 Aug. 2017
These zoologists know how to navigate the untamed land, accurately identify diurnal and nocturnal creatures and place covert camera traps to photograph the most elusive wildlife.

— kyle frischkorn, Smithsonian, "How Fly Guts Help Researchers Catalog the Rainforest," 7 Aug. 2017
During the summer months, strong and damaging winds are the most likely severe weather threat associated with these summertime, diurnal storms.

— kathryn prociv, Washington Post, "Pic of the week: Green monster swallows the sky over Pennsylvania," 2 Aug. 2017
The sharks have been found in shallow waters near the water's surface and ocean depths of up to a mile, suggesting the animals are diurnal, and regularly alternate between deep and shallow.

— National Geographic, "Rare Megamouth Shark Captured on Video," 26 July 2017
Evidence suggests that a similar extravaganza of protein creation and destruction occurs in the human liver, too, but the timing is flipped to match our largely diurnal pattern.

— natalie angier, New York Times, "The Liver: A ‘Blob’ That Runs the Body," 12 June 2017

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.