solar day

noun

Definition of solar day

: 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 One solar day—a full day-night cycle—takes 176 Earth days. Jennifer Leman, Popular Mechanics, "Small Yet Mighty Mercury Still Holds Many Mysteries," 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, "Polar Light," 10 Jan. 2019 In the 1980s and 1990s, the three scientists who received the award figured out how genetic time counters in cells aligned biological function to the 24-hour solar day. Jacqueline Detwiler, Popular Mechanics, "Why You Should Have Heart Surgery in the Afternoon," 26 Dec. 2018 The length of a solar day, measured by the time between the sun’s passage of any particular point in the sky, is rarely 24 hours precisely. Scott Dance, baltimoresun.com, "Baltimore's earliest sunrise of the year comes Thursday," 13 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'solar day.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of solar day

1751, in the meaning defined above

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Time Traveler for solar day

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The first known use of solar day was in 1751

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Cite this Entry

“Solar day.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/solar%20day. Accessed 27 Jan. 2021.

More from Merriam-Webster on solar day

Britannica.com: Encyclopedia article about solar day

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