GNU Collaborative International Dictionary of English

Found 2 definitions

1.       
   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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2.       
   Nocturnal, n. An instrument formerly used for taking the altitude of the stars, etc., at sea.  I. Watts.
   
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