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diurnal

Syllabification: di·ur·nal
Pronunciation: /dīˈərnl
 
/

Definition of diurnal in English:

adjective

1Of or during the day.
Example sentences
  • 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.
1.1 Zoology (Of animals) active in the daytime.
Example sentences
  • 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.
1.2 Botany (Of flowers) open only during the day.
Example sentences
  • 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.
2Daily; of each day: diurnal rhythms
More example sentences
  • 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.
2.1 Astronomy Of or resulting from the daily rotation of the earth.
Example sentences
  • 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.

Origin

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

Derivatives

diurnally

1
adverb
Example sentences
  • Experimenters have established the use of a time-compensated sun-compass by homing pigeons and diurnally migrating songbirds.
  • Males fly readily both diurnally and nocturnally.
  • Nocturnal migrants following coasts and diurnally mobile individuals may also be channeled into those peninsular areas.

Definition of diurnal in:

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Pronunciation: ˈtɛnɪbrəs
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