Nocturnal (?), a. [L. nocturnalis, nocturnus, fr. nox, noctis, night. See Night, and cf. Nocturn.] 1. Of, pertaining to, done or occuring in, the night; as, nocturnal darkness, cries, expedition, etc.; -- opposed to diurnal. Dryden.
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2. Having a habit of seeking food or moving about at night; as, nocturnal birds and insects; raccoons are nocturnal.; -- of animals.
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