mean solar day

mean solar day

n. The period of time between two successive transits of the mean sun, used as the standard in measuring the 24-hour day.

mean solar day

n (Astronomy) the time between two successive passages of the mean sun across the meridian at noon. It is equal to 24 hours 3 minutes and 56.555 seconds of mean sidereal time

day

(deɪ)

n. 1. the interval of light between two successive nights; the time between sunrise and sunset. 2. the light of day; daylight. 3. a. Also called mean solar day. a division of time equal to 24 hours and representing the average length of the period during which the earth makes one rotation on its axis. b. Also called solar day. a division of time equal to the time elapsed between two consecutive returns of the same terrestrial meridian to the sun. c. a division of time equal to 24 hours but reckoned from one midnight to the next. 4. an analogous division of time for a planet other than the earth: the Martian day. 5. the portion of a day allotted to work: an eight-hour day. 6. (often cap.) a day having a particular purpose or observance: New Year's Day. 7. a time considered as propitious or opportune: His day will come. 8. Often, days. a particular era: in olden days. 9. Usu., days. period of life or activity: His days are numbered. 10. period of existence or influence; heyday: In my day we called them “hepcats.” 11. the contest or battle at hand: to win the day. Idioms: 1. call it a day, to stop working for the rest of the day. 2. day in, day out, every day without fail; regularly. Also, day in and day out. [before 950; Middle English; Old English dæg]

mean solar day

A measure of time representing the interval between consecutive passages of the Sun across the meridian, averaged over one year. 1 day = 24 hr (86,400 sec).

Thesaurus

Noun

1.

mean solar day - time for Earth to make a complete rotation on its axis; "two days later they left"; "they put on two performances every day"; "there are 30,000 passengers per day"24-hour interval, day, solar day, twenty-four hour period, twenty-four hourstime unit, unit of time - a unit for measuring time periodstomorrow - the day after today; "what are our tasks for tomorrow?"today - the day that includes the present moment (as opposed to yesterday or tomorrow); "Today is beautiful"; "did you see today's newspaper?"yesterday - the day immediately before today; "it was in yesterday's newspapers"morrow - the next day; "whenever he arrives she leaves on the morrow"eve - the day before; "he always arrives on the eve of her departure"date, day of the month - the specified day of the month; "what is the date today?"date - a particular day specified as the time something happens; "the date of the election is set by law"daylight, daytime, day - the time after sunrise and before sunset while it is light outside; "the dawn turned night into day"; "it is easier to make the repairs in the daytime"high noon, midday, noon, noonday, noontide, twelve noon - the middle of the daynight, nighttime, dark - the time after sunset and before sunrise while it is dark outside60 minutes, hour, hr - a period of time equal to 1/24th of a day; "the job will take more than an hour"