Definition of diurnal
(Entry 1 of 2)
1a
biology
: active chiefly in the daytime
diurnal animals
b
: of, relating to, or occurring in the daytime
the city's diurnal noises
c
botany
: opening during the day and closing at night
diurnal flowers
2a
: recurring every day
diurnal tasks
b
: having a daily cycle
diurnal tides
diurnal
nounDefinition of diurnal (Entry 2 of 2)
1
: journal sense 1a
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Merriam-Webster unabridged
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Time Traveler for diurnal
The first known use of diurnal was in the 14th century
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