diurnal

di•ur•nal (dahy-UR-nl)  adj

Definition:
1. of or pertaining to a day or each day; daily
2. of or belonging to the daytime
3. showing a periodic alteration of condition with day and night, as certain flowers that open by day and close by night (botany)
4. active by day, as certain birds and insects ( opposed to nocturnal)
5. a service book containing offices for the daily hours of prayer (liturgy)
6. a diary (archaic)
7. a newspaper, esp. a daily one (archaic)

diurnalness noun;  diurnally adverb

Origin:
late 14c., from L.L. diurnalis "daily," from L. dies "day" + -urnus, an adj. suffix denoting time.  Dies "day" is from PIE base *dyeu-  lit. "to shine"

Related:
transdiurnal, undiurnal 
Synonyms: circadian, daily, everyday, quotidian
Related Words: quotidian, circadian, diary, diet, per diem, meridian, dial, dismal

Sentence Examples:
• The early astronomers had, moreover, learned to recognise the fixed stars. It was noticed that, like the sun, many of these stars rose and set in consequence of the diurnal movement, while the moon obviously followed a similar law. -The Story of the Heavens, Robert Stawell Ball

• Rabbits and hares are crepuscular and possibly more nocturnal than diurnal. So far as I know they do not store food as do their diurnal relatives, the pikas. -A Synopsis of the North American Lagomorpha, E. Raymond Hall

• He has adhered to the diurnal form of narrative, for the sake of recording, for the benefit of future travellers, the numbers, marks, latitude, etc., of each camp, and endeavoured to compass by this composite method the value of a work of record with the interest of a narrative. -The Overland Expedition of The Messrs. Jardine, Frank Jardine and Alexander Jardine

The Storyline
As she contemplated, she began to fall into her diurnal routine.

Sources: Dictionary.com, Online Etymology

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