Diurnal ("daily") may refer to:
- Diurnal cycle, any pattern that recurs daily
- Diurnality, the behavior of animals and plants that are active in the daytime
- Diurnal motion, the apparent motion of stars around the Earth
- Diurnal phase shift, a phase shift of electromagnetic signals
- Diurnal temperature variation, a cycle of daily temperature change
In astrology:
- Diurnal chart, a chart for a given date, based on the natal chart
- Diurnal planet, a planet in a sect for which the Sun is above the horizon
- Diurnal sign, a sign in the zodiac
- Diurnal arc, time expressed as right ascension
Famous quotes containing the word diurnal:
“No motion has she now, no force;
She neither hears nor sees;
Rolled round in earth’s diurnal course,
With rocks, and stones, and trees.”
—William Wordsworth (1770–1850)