Meaning of diurnal in English:


Pronunciation /dʌɪˈəːn(ə)l/

See synonyms for diurnal

Translate diurnal into Spanish


  • 1Of or during the day.

    ‘When I was first married I was practically nocturnal, and my wife was diurnal.’
    • ‘It's now 6am, which is the equivalent of 6pm for all of those conservative diurnal types.’
    • ‘I'll get maybe three, four good diurnal emissions off per day, I reckon.’
    • ‘The mercury levels now seem to have changed with diurnal temperature difference narrowing down.’
    • ‘A feature shared by many clock gene transcripts is that their abundance is subject to circadian and diurnal oscillation.’
    active during the day, non-nocturnal
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    1. 1.1Zoology (of animals) active in the daytime.
      ‘They are diurnal herbivores, hiding in reef crevices during nighttime and browsing over reefs to feed during the day.’
      • ‘Conversely, subdominant fish were diurnal and occupied large home ranges by day but were generally not observed at night.’
      • ‘Accipitrids are diurnal birds of prey with broad wings, hooked beaks, strong legs and feet and sharp talons.’
      • ‘The male provides no direct parental care except to protect the eggs against diurnal fish predators.’
      • ‘Finally, group living often provides diurnal rodents with better predator defenses.’
    2. 1.2Botany (of flowers) open only during the day.
      ‘Are diurnal changes of turgor and leaf growth correlated with each other?’
      • ‘Ammonium concentrations in roots and leaves undergo diurnal changes.’
      • ‘NRA showed important diurnal changes in leaves and roots tissues.’
      • ‘There are only marginal changes in phosphorylated intermediates in the diurnal time-frame or during tuber development.’
      • ‘The sample traces (a, b) are representative of the diurnal pattern of leaf extension rate for each species.’
  • 2Daily; of each day.

    ‘diurnal rhythms’
    • ‘Universal, reliable and even human-made light, completely independent of diurnal rhythm, has abolished the shamanist aspects of our calling.’
    • ‘This apparently inefficient system gives us the ability to deal with the natural variability of the diurnal rhythms of light and temperature.’
    • ‘The diurnal rhythm of cortisol secretion in the horse peaks at approximately 0600 h and is least at approximately 1800 h.’
    • ‘Moreover, while minor amino acids show marked diurnal rhythms, their contents fluctuate in a co-ordinated manner.’
    • ‘The APR of maize and Arabidopsis thaliana follows a diurnal rhythm with maximum activity during the light period.’
    • ‘The absence of a diurnal rhythm would be a significant difference between growth control in roots and dicot leaves.’
    • ‘Experiments were performed always at the same time of the day, to avoid interference with diurnal rhythms.’
    • ‘The transporters show different expression patterns in response to diurnal rhythm.’
    • ‘This impulse to explore the diurnal is shared by cinema which similarly took everyday objects and put them on exhibit as a form of ‘art’.’
    • ‘For the most part, this diurnal ritual occurs around 6: 30 a.m.’
    • ‘What I needed for recovery was a long period of rest in a comfortable setting with a familiar diurnal schedule.’
    • ‘Her diurnal ritual of hurriedly brushing her hair before the mirror expands to one of self-admiration.’
    • ‘They have their own diurnal cycles, pegged to alien time-frames.’
    • ‘Today FM, for example, operates to a finely calibrated diurnal rhythm, carefully tuned to the mood of its audience.’
    • ‘Too late for conventional diurnal rhythms; too early for genuine nocturnal ones.’
    daily, everyday, day-to-day, quotidian
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    1. 2.1Astronomy Of or resulting from the daily rotation of the earth.
      ‘diurnal aberration’
      • ‘Magnetism, in other words, caused the Earth's Copernican diurnal rotation.’
      • ‘In poetic form, Aryabhata stated that the earth's diurnal rotation on its axis produced the daily rising and setting of planets and stars.’
      • ‘Right ascension makes it easy to use the apparent diurnal rotation of the celestial sphere as a means to telling time.’
      • ‘He explained eclipses, solstices and equinoxes, announced the sphericity of the earth and its diurnal revolution on its axis.’
      • ‘What mattered was the planet's diurnal position relative to the horizon - whether it was rising in the east or culminating overhead.’


Late Middle English (as a term in astronomy): from late Latin diurnalis, from Latin diurnus ‘daily’, from dies ‘day’.