What is the meaning of Diurnal?

Happening or occurring during daylight, or primarily active during that time.

Said of a flower that is open, or releasing its perfume during daylight hours, but not at night.

Having a daily cycle that is completed every 24 hours, usually referring to tasks, processes, tides, or sunrise to sunset; circadian.

Done once every day; daily, quotidian.

Published daily.

A flower that opens only in the day.

A book containing canonical offices performed during the day, hence not matins.

A diary or journal.

A daily news publication.

diurnal (book)

diurnal

diurnal

Source: wiktionary.org