nocturnal
adjective
noc·tur·nal
näk-ˈtər-nᵊl 
1
: of, relating to, or occurring in the night
a nocturnal journey
nocturnal activities
2
: active at night
a nocturnal predator
nocturnal insects, such as mosquitoes
Examples of nocturnal in a Sentence
he bought a new telescope so he could pursue his favorite nocturnal hobby of astronomy
Recent Examples on the Web
How the Squirrel Left the Mark Seth Magle, director of the Lincoln Park Zoo’s Urban Wildlife Institute, noted that concrete is usually poured during the day, when squirrels are active, while rats are nocturnal.
—
Alice Gibbs, MSNBC Newsweek, 14 Oct. 2025
Beyond astronomy, the continuous illumination could disrupt the delicate daily rhythms of nocturnal animals, impacting ecosystems worldwide.
—Mrigakshi Dixit, Interesting Engineering, 13 Oct. 2025
During the total solar eclipse of 2017, scientists observed the reactions of zoo animals, with some birds returning to evening roosts while nocturnal species became more active.
—Ashley Strickland, CNN Money, 13 Oct. 2025
Payton found an ally in running back Walker, who had absorbed football’s complex verbiage during his nocturnal Sunday nights.
—Peter Carline, New York Times, 10 Oct. 2025
See All Example Sentences for nocturnal
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Alice Gibbs, MSNBC Newsweek, 14 Oct. 2025
Beyond astronomy, the continuous illumination could disrupt the delicate daily rhythms of nocturnal animals, impacting ecosystems worldwide.
—Mrigakshi Dixit, Interesting Engineering, 13 Oct. 2025
During the total solar eclipse of 2017, scientists observed the reactions of zoo animals, with some birds returning to evening roosts while nocturnal species became more active.
—Ashley Strickland, CNN Money, 13 Oct. 2025
Payton found an ally in running back Walker, who had absorbed football’s complex verbiage during his nocturnal Sunday nights.
—Peter Carline, New York Times, 10 Oct. 2025
See All Example Sentences for nocturnal
Cite this Entry
“Nocturnal.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/nocturnal. Accessed 20 Oct. 2025.
Copy CitationKids Definition
nocturnal
adjective
noc·tur·nal
näk-ˈtərn-ᵊl
1
: of, relating to, or occurring in the night
a nocturnal journey
2
: active at night
nocturnal insects
Etymology
from early French nocturnal, nocturnel or Latin nocturnalis, both meaning "nocturnal," derived from earlier Latin noct-, nox "night" — related to equinox
Medical Definition
nocturnal
adjective
noc·tur·nal
näk-ˈtərn-ᵊl
1
: of, relating to, or occurring at night
nocturnal myoclonus
2
: characterized by nocturnal activity
a nocturnal form of filariasis
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