Simple Definition of nocturnal

from our Learner's Dictionary

nocturnal

adjective

nɑkˈtɚnl̟

1

: active mainly during the night

nocturnal animals

2

formal : happening at night

a nocturnal journey

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“Nocturnal.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/nocturnal. Accessed 18 Jun. 2026.

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