Definition of nocturnal in English:

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Pronunciation: /nɒkˈtəːn(ə)l/


Done, occurring, or active at night: most owls are nocturnal
More example sentences
  • Max has the night beat, circling a nocturnal but always active Los Angeles.
  • Prior to my night of nocturnal mutterings two other rather aggravating events took place.
  • The second reason for the interest in owls is that they are beautiful to look at and most of them are nocturnal which means that they hunt at night.



Example sentences
  • While the light environment of shallow water crustaceans may vary dramatically on a 24 hour cycle, deep-sea species live in a much more constant light environment, similar to that of nocturnally active insects.
  • Also, some prey species in both freshwater and saltwater environments are more active nocturnally than diurnally, this increasing their likelihood of capture by nocturnal-foraging Wood Storks.
  • In nocturnally feeding waterfowl, increased feeding rates were found during daytime in seasons when nights were short, indicating that birds were compensating for restricted feeding periods.


Late 15th century: from late Latin nocturnalis, from Latin nocturnus 'of the night', from nox, noct- 'night'.

  • night from Old English:

    Although an Old English word, night comes ultimately from the same root as Latin nox, the source of equinox (Late Middle English) and nocturnal (Late Middle English). Fortnight (Old English) is an Old English contraction of ‘fourteen nights’, and reflects an ancient Germanic custom of reckoning time by nights rather than days. The original night of the long knives was the legendary massacre of the Britons by the Saxon leader Hengist in 472. According to the 12th-century Welsh chronicler Geoffrey of Monmouth, the Saxons attended a meeting armed with long knives, and when a prearranged signal was given each Saxon drew his weapon and killed the Briton seated next to him. The phrase is now more commonly associated with the brutal suppression of the Brownshirts (a Nazi militia replaced by the SS) on Hitler's orders in 1934. It is also used of any decisive or ruthless sacking, in particular the occasion in 1962 when British Prime Minister Harold Macmillan dismissed a third of his cabinet at the same time. Nightmares are nothing to do with horses. In the Middle Ages a nightmare (Middle English) was thought of as an evil female spirit or monster that lay on sleeping people and suffocated them: the -mare part comes from Old English and meant ‘suffocating evil spirit’.

Words that rhyme with nocturnal

colonel, diurnal, eternal, external, fraternal, infernal, internal, journal, kernel, maternal, paternal, supernal, vernal

For editors and proofreaders

Line breaks: noc|tur¦nal

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