diurnal

adj

1. (not-comparable)Happening or occurring during daylight, or primarily active during that time.

   “Most birds are diurnal.”

   “However, in general, lizards are more diurnal than rattlers, which may be one of the reasons why young rattlers are more diurnal than adults.”

   “Ere twice the horses of the sun shall bring / Their fiery torcher his diurnal ring.”

2. (not-comparable)Said of a flower that is open, or releasing its perfume during daylight hours, but not at night.
3. (not-comparable)Having a daily cycle that is completed every 24 hours, usually referring to tasks, processes, tides, or sunrise to sunset; circadian.
4. (not-comparable, uncommon)Done once every day; daily, quotidian.
5. (archaic, not-comparable)Published daily.

noun

1. A flower that opens only in the day.
2. A book containing canonical offices performed during the day, hence not matins.
3. (archaic)A diary or journal.

   “He was by birth, some authors write, / A Russian, some a Muscovite, / And 'mong the Cossacks had been bred, / Of whom we in diurnals read.”

4. (archaic)A daily news publication.