diurnal

[ dahy-ur-nl ]

adjective

1. of or relating to a day or each day; daily.
2. of or belonging to the daytime ( nocturnal ).
3. Botany. showing a periodic alteration of condition with day and night, as certain flowers that open by day and close by night.
4. active by day, as certain birds and insects ( nocturnal ).

noun

1. Liturgy. a service book containing offices for the daily hours of prayer.
2. Archaic. a diary.
3. Archaic. a newspaper, especially a daily one.

diurnal

/ daɪˈɜːnəl /

adjective

1. happening during the day or daily
2. (of flowers) open during the day and closed at night
3. (of animals) active during the day Compare nocturnal

noun

1. a service book containing all the canonical hours except matins

diurnal

/ dī-ûr′nəl /

1. 1. Occurring once in a 24-hour period; daily.
   2. Having a 24-hour cycle. The movement of stars and other celestial objects across the sky are diurnal.
2. Most active during the daytime. Many animals, including the apes, are diurnal.
3. Having leaves or flowers that open in daylight and close at night. The morning glory and crocus are diurnal.
4. Compare nocturnal

Derived Forms

• diˈurnally, adverb

Other Words From

• di·urnal·ly adverb
• di·urnal·ness noun
• transdi·urnal adjective
• undi·urnal adjective
• undi·urnal·ly adverb

Word History and Origins

Origin of diurnal¹

1400–50; late Middle English < Latin diurnālis, equivalent to diurn ( us ) daily + -ālis -al ¹

Word History and Origins

Origin of diurnal¹

C15: from Late Latin diurnālis, from Latin diurnus, from diēs day

Example Sentences

I think future studies will reveal many plant species that are thought to be dependent on pollination by diurnal insects are indeed pollinated by nocturnal moths, to some extent.

From Science News

With the help of a therapist, she developed a more diurnal schedule that allowed her to get work done while maintaining a social life.

From Time

The diurnal rotation of the Earth is effected round this axis.

From Project Gutenberg

He accomplishes his diurnal revolution in less than ten hours!

From Project Gutenberg

A son of the first king suggested the plan of giving the sun diurnal movement and the changing light.

From Project Gutenberg

Drymobius margaritiferus margaritiferus is diurnal and terrestrial; it feeds on frogs at the edges of breeding ponds by day.

From Project Gutenberg

All of these are diurnal, and all but Laemanctus have been observed sleeping on bushes at night.

From Project Gutenberg

Related Words

• constantly
• day-to-day
• everyday
• often
• periodic
• regular
• regularly
• routine