solar day
noun
: the interval between transits of the apparent or mean sun across the meridian at any place
Examples of solar day in a Sentence
Recent Examples on the Web
Since official records began in 1973, Earth's solar day has been steadily lengthening, mostly due to the moon.
—
Jamie Carter, Space.com, 5 Aug. 2025
How long is a normal day on Earth? People live by the 24-hour solar day on Earth.
—Hannah Poukish, Sacbee.com, 5 Aug. 2025
Near the December solstice, each solar day runs about 24 hours and 30 seconds long.
—Justin Grieser, Anchorage Daily News, 21 Dec. 2022
The first division of the day’s 24 hours (known in Latin as partes minutae primae) gave them the length of the minute, which was one-1,440th of an average solar day.
—New York Times, 25 Apr. 2022
If a person doesn’t get enough exposure to daytime light, perhaps due to long hours at school or the office, misalignment between the various clocks and the solar day can set off cascading effects.
—Carla Delgado, Discover Magazine, 29 Mar. 2022
When deprived of information from the outside world, the sleep-wake cycle usually lagged slightly slower than the solar day, with a period averaging around 25 hours.
—Jo Marchant, Wired, 1 Sep. 2020
One solar day—a full day-night cycle—takes 176 Earth days.
—Jennifer Leman, Popular Mechanics, 9 Nov. 2019
It’s eleven-thirty at night according to my watch, but this far south the hour of the solar day is of no help in trying to understand the situation we’re in here, or our work rhythms.
—Barry Lopez, Harper's magazine, 10 Jan. 2019
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Jamie Carter, Space.com, 5 Aug. 2025
How long is a normal day on Earth? People live by the 24-hour solar day on Earth.
—Hannah Poukish, Sacbee.com, 5 Aug. 2025
Near the December solstice, each solar day runs about 24 hours and 30 seconds long.
—Justin Grieser, Anchorage Daily News, 21 Dec. 2022
The first division of the day’s 24 hours (known in Latin as partes minutae primae) gave them the length of the minute, which was one-1,440th of an average solar day.
—New York Times, 25 Apr. 2022
If a person doesn’t get enough exposure to daytime light, perhaps due to long hours at school or the office, misalignment between the various clocks and the solar day can set off cascading effects.
—Carla Delgado, Discover Magazine, 29 Mar. 2022
When deprived of information from the outside world, the sleep-wake cycle usually lagged slightly slower than the solar day, with a period averaging around 25 hours.
—Jo Marchant, Wired, 1 Sep. 2020
One solar day—a full day-night cycle—takes 176 Earth days.
—Jennifer Leman, Popular Mechanics, 9 Nov. 2019
It’s eleven-thirty at night according to my watch, but this far south the hour of the solar day is of no help in trying to understand the situation we’re in here, or our work rhythms.
—Barry Lopez, Harper's magazine, 10 Jan. 2019
Cite this Entry
“Solar day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/solar%20day. Accessed 30 Oct. 2025.
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