Definition of diurnal:
- A daybook; a journal.
- A diurnal bird or insect.
- A small volume containing the daily service for the little hours, viz., prime, tierce, sext, nones, vespers, and compline.
- Active by day; - applied especially to the eagles and hawks among raptorial birds, and to butterflies ( Diurna) among insects.
- 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.
- Opening during the day, and closing at night; - said of flowers or leaves.
- Relating to the daytime; belonging to the period of daylight, distinguished from the night; - opposed to nocturnal; as, diurnal heat; diurnal hours.
During the day the animals obsequiously followed the shadow of the smallest tree as it moved round the stem with the diurnal roll; and when the milkers came they could hardly stand still for the flies.- "Tess of the d'Urbervilles A Pure Woman", Thomas Hardy.
- "Directions for Collecting and Preserving Insects", C. V. Riley.
- "Quodlibet", John P. Kennedy.