The definition of nocturnal is something that is active or happens during the night.(adjective)
An example of a nocturnal animal is a bat.
See nocturnal in Webster's New World College Dictionary
Origin: LME < LL nocturnalis < L nocturnus < nox (gen. noctis), night
See nocturnal in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old French
Origin: , from Late Latin nocturnālis
Origin: , from Latin nocturnus
Origin: , from nox, noct-, night; see nekw-t- in Indo-European roots.
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