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

nocturnally

näk-ˈtər-nᵊl-ē 

adverb

Synonyms

• night
• nightly
• nighttime

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

And because each of these stories takes place in the dead of night, Swift and Jack Antonoff have constructed a nocturnal aesthetic for Midnights, full of bass-heavy midtempo beats and heavily reverbed synths. —Al Shipley, SPIN, 5 May 2024

The artwork, which juxtaposes a nocturnal lamplit street with a serene daylit sky, is one of the most celebrated and enigmatic images in 20th-century art. —Alex Vadukul, New York Times, 3 May 2024

The blossom's smell attracts nocturnal pollinators, including bats and moths. —Laura Daniella Sepulveda, The Arizona Republic, 3 May 2024

The scientists found that the ants' nocturnal rest phase and daily activity was suppressed ahead of seismic activity, and their standard daily routine did not resume until the next day. —Julia Jacobo, ABC News, 2 May 2024

Creeping through the forests of Thailand, the nocturnal predator hunts under the cover of darkness. —Irene Wright, Miami Herald, 1 May 2024

Owls, the nocturnal bird, started flying in circles and clawing at the cage right as the sky was turning dark. —Ella Gonzales, Fort Worth Star-Telegram, 12 Apr. 2024

During solar eclipses, when the sky briefly turns dark, dogs may cower, birds stop flying and grow quiet, and nocturnal creatures emerge. —Mallory Moench, TIME, 7 Apr. 2024

What is not clear is what happens to nocturnal animals when the eclipse occurs, Speck said. —Julia Jacobo, ABC News, 3 Apr. 2024

Word History

Etymology

Middle English, borrowed from Anglo-French & Late Latin; Anglo-French nocturnel, borrowed from Late Latin nocturnālis "for night use," from Latin nocturnus "of or occurring at night" (from noct-, nox night entry 1 + -urnus, temporal suffix, as in diurnus "of the day") + -ālis -al entry 1 — more at journal

First Known Use

15th century, in the meaning defined at sense 1

Kids 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

nocturnally

-ᵊl-ē 

adverb

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