diurnal

1 of 2

adjective

di·​ur·​nal dī-ˈər-nᵊl How to pronounce diurnal (audio)
1
a
biology : active chiefly in the daytime
diurnal animals
b
: of, relating to, or occurring in the daytime
the city's diurnal noises
c
botany : opening during the day and closing at night
diurnal flowers
2
a
: recurring every day
diurnal tasks
b
: having a daily cycle
diurnal tides
diurnally adverb

diurnal

2 of 2

noun

1
2
archaic : diary, daybook

Examples of diurnal in a Sentence

Adjective a love as constant and certain as the diurnal tides Noun a collection of diurnals containing essays by preeminent 19th-century American writers and thinkers
Recent Examples on the Web
Adjective
Frogs and crickets, common elements of an evening soundscape, started to call, while diurnal cicadas stopped making noise. Carlyn Kranking, Smithsonian Magazine, 5 Apr. 2024 The diurnal asymmetric warming of the earth has reversed course since 1991, with daytime temperatures rising faster than nighttime ones. Frederick Kaufman, Harper's Magazine, 26 Feb. 2024 But where owls have evolved to overcome darkness, the diurnal raptors excel at overcoming distance, the second great limit to our vision. Jack Gedney, The Mercury News, 11 Mar. 2024 One question researchers want to answer is whether nocturnal and diurnal animals act differently or become more or less vocal during a solar eclipse. Jamie Carter, Forbes, 13 Feb. 2024 The question of whether dinosaurs were nocturnal (active at night) or diurnal (active during the day) is complex, as dinosaurs were a highly diverse group of animals. Sara Novak, Discover Magazine, 14 Dec. 2023 That, along with a good diurnal shift in temperature, helps keep the wine fresh. Lana Bortolot, Forbes, 30 Nov. 2023 The most significant shift was in cheetahs, a typically diurnal species -- or one that spends its awake hours during the day -- the researchers said. Julia Jacobo, ABC News, 7 Nov. 2023 How Do Frogs See? Scientists from the Natural History Museum, have discovered a connection between frogs that are active during the day (diurnal frogs) and the development of lenses in their eyes. Katie Liu, Discover Magazine, 26 Oct. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'diurnal.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

Etymology

Adjective

Middle English, from Latin diurnalis — more at journal

Noun

derivative of diurnal entry 1

First Known Use

Adjective

14th century, in the meaning defined at sense 2a

Noun

1600, in the meaning defined at sense 2

Time Traveler
The first known use of diurnal was in the 14th century

Podcast

Dictionary Entries Near diurnal

Cite this Entry

“Diurnal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/diurnal. Accessed 21 Apr. 2024.

Kids Definition

diurnal

adjective
di·​ur·​nal
dī-ˈərn-ᵊl
1
: occurring every day : daily
a diurnal task
2
a
: of, relating to, or occurring in the daytime
the city's diurnal noises
b
: active chiefly in the daytime
diurnal animals
diurnally
-ˈərn-ᵊl-ē
adverb

Medical Definition

diurnal

adjective
di·​ur·​nal dī-ˈərn-ᵊl How to pronounce diurnal (audio)
1
: having a daily cycle
diurnal rhythms
2
a
: of, relating to, or occurring in the daytime
diurnal activity
b
: chiefly active during the daytime
diurnal mosquitoes
diurnally adverb

More from Merriam-Webster on diurnal

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!