DIURNAL

adj a daybook; a journal.

2. diurnal ·adj a diurnal bird or insect.

3. diurnal ·adj opening during the day, and closing at night;

— said of flowers or leaves.

4. diurnal ·adj a small volume containing the daily service for the "little hours," viz., prime, tierce, sext, nones, vespers, and compline.

5. diurnal ·adj active by day;

— applied especially to the eagles and hawks among raptorial birds, and to butterflies (diurna) among insects.

6. diurnal ·adj relating to the daytime; belonging to the period of daylight, distinguished from the night;

— opposed to nocturnal; as, diurnal heat; diurnal hours.

7. diurnal ·adj daily; recurring every day; performed in a day; going through its changes in a day; constituting the measure of a day; as, a diurnal fever; a diurnal task; diurnal aberration, or diurnal parallax; the diurnal revolution of the earth.