The Collaborative International Dictionary
Day \Day\ (d[=a]), n. [OE. day, dai, dei, AS. d[ae]g; akin to OS., D., Dan., & Sw. dag, G. tag, Icel. dagr, Goth. dags; cf. Skr. dah (for dhagh ?) to burn. [root]69. Cf. Dawn.]
The time of light, or interval between one night and the next; the time between sunrise and sunset, or from dawn to darkness; hence, the light; sunshine; -- also called daytime.
The period of the earth's revolution on its axis. -- ordinarily divided into twenty-four hours. It is measured by the interval between two successive transits of a celestial body over the same meridian, and takes a specific name from that of the body. Thus, if this is the sun, the day (the interval between two successive transits of the sun's center over the same meridian) is called a solar day; if it is a star, a sidereal day; if it is the moon, a lunar day. See Civil day, Sidereal day, below.
Those hours, or the daily recurring period, allotted by usage or law for work.
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A specified time or period; time, considered with reference to the existence or prominence of a person or thing; age; time.
A man who was great among the Hellenes of his day.
--Jowett (Thucyd. )If my debtors do not keep their day, . . . I must with patience all the terms attend.
--Dryden. -
(Preceded by the) Some day in particular, as some day of contest, some anniversary, etc. The field of Agincourt, Fought on the day of Crispin Crispianus. --Shak. His name struck fear, his conduct won the day. --Roscommon. Note: Day is much used in self-explaining compounds; as, daybreak, daylight, workday, etc. Anniversary day. See Anniversary, n. Astronomical day, a period equal to the mean solar day, but beginning at noon instead of at midnight, its twenty-four hours being numbered from 1 to 24; also, the sidereal day, as that most used by astronomers. Born days. See under Born. Canicular days. See Dog day. Civil day, the mean solar day, used in the ordinary reckoning of time, and among most modern nations beginning at mean midnight; its hours are usually numbered in two series, each from 1 to 12. This is the period recognized by courts as constituting a day. The Babylonians and Hindoos began their day at sunrise, the Athenians and Jews at sunset, the ancient Egyptians and Romans at midnight. Day blindness. (Med.) See Nyctalopia. Day by day, or Day after day, daily; every day; continually; without intermission of a day. See under By. ``Day by day we magnify thee.'' --Book of Common Prayer. Days in bank (Eng. Law), certain stated days for the return of writs and the appearance of parties; -- so called because originally peculiar to the Court of Common Bench, or Bench (bank) as it was formerly termed. --Burrill. Day in court, a day for the appearance of parties in a suit. Days of devotion (R. C. Ch.), certain festivals on which devotion leads the faithful to attend mass. --Shipley. Days of grace. See Grace. Days of obligation (R. C. Ch.), festival days when it is obligatory on the faithful to attend Mass. --Shipley. Day owl, (Zo["o]l.), an owl that flies by day. See Hawk owl. Day rule (Eng. Law), an order of court (now abolished) allowing a prisoner, under certain circumstances, to go beyond the prison limits for a single day. Day school, one which the pupils attend only in daytime, in distinction from a boarding school. Day sight. (Med.) See Hemeralopia. Day's work (Naut.), the account or reckoning of a ship's course for twenty-four hours, from noon to noon. From day to day, as time passes; in the course of time; as, he improves from day to day. Jewish day, the time between sunset and sunset. Mean solar day (Astron.), the mean or average of all the apparent solar days of the year. One day, One of these days, at an uncertain time, usually of the future, rarely of the past; sooner or later. ``Well, niece, I hope to see you one day fitted with a husband.'' --Shak. Only from day to day, without certainty of continuance; temporarily. --Bacon. Sidereal day, the interval between two successive transits of the first point of Aries over the same meridian. The Sidereal day is 23 h. 56 m. 4.09 s. of mean solar time. To win the day, to gain the victory, to be successful. --S. Butler. Week day, any day of the week except Sunday; a working day. Working day.
A day when work may be legally done, in distinction from Sundays and legal holidays.
The number of hours, determined by law or custom, during which a workman, hired at a stated price per day, must work to be entitled to a day's pay.
WordNet
n. the period of time taken for the moon to make one full rotation on its axis (about 27.3 sidereal days)
Wikipedia
A lunar day is the period of time it takes for the Earth's Moon to complete one full rotation on its axis with respect to the Sun. Equivalently, it is the time it takes the Moon to make one complete orbit around the Earth and come back to the same phase. It is marked from a new moon to the next new moon.
With respect to the stars, the Moon takes 27 Earth days, 7 hours and 43 minutes 12 seconds to complete its orbit; but since the Earth-Moon system advances around the Sun in the meantime, the Moon must travel further to get back to the same phase. On average(mean), this synodic period lasts 29 days, 12 hours, 44 minutes and 3 seconds. This is an average figure, since the speed of the Earth-Moon system around the Sun varies slightly during a year, due to an imperfect circularity of its orbit, variances in orbital velocity, and a number of other periodic and evolving variations about its observed, relative, mean values, due to the gravitational perturbations of the Sun and other bodies in the Solar System.
As a result, daylight at a given point on the Moon would last approximately two weeks from beginning to end, followed by approximately two weeks of night.
Usage examples of "lunar day".
During the long lunar day, here in Landsberg, the sky was royal blue and full of fish: goldfish and carp.
Our bubble helmets had darkened and our eyes had adjusted to lunar day.
The deep black shadows at the foot of the mountains to his left were lengthening as the two-week-long lunar day drew to its close.
Though the lunar day had barely started, the Mountains were already burning.
For many people, such visits were the peak of each slow lunar Day.
Three daycycles after she reached the mine, about one-tenth of a Lunar day, the disaster happened.
Moore says he has enough food-syrup on hand to last the rest of our stay here, but will continue work for a while next lunar day.
Not only that, but the glass manufacturing operations were proceeding apace: plants had been set up all over the bare soil of Clavius Crater, so that streams of components poured into the Sling's launching bay by lunar day and night.
They had power for perhaps four days more, thanks to the fact that the long Lunar day had begun shortly after Gresth Gkae's impatient attack had started.
It should be possible to move them around as the lunar day progresses.
The old NASA plans always showed astronauts colonizing a polar crater, somewhere you could catch the sun all lunar day, and where there would be ice to mine.