Dāy (dā), n.

(dā), n. [A-S. dæg, O. Sax., D., Dan., & Sw. dag, Icel. dagr, Goth. dags, Ger. tag, Ir. dia, W. dydd, dyw, Armor. deiz, déz, Lat. dies, Skr. dyu, from dyu, div, to shine.]

1Sense 1. The interval between one night and the next; the period from sunrise to sunset, or from dawn to darkness; hence, the light; sunshine.

The fire That severs day from night. Shak.

2Sense 2. 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 is called a solar day; if it is a star, a sidereal day; if it is the moon, a lunar day.

3Sense 3. A specified time or period; time considered with reference to the existence or prominence of a person or thing. “He was useful in his day.” “The fashion has had its day.”

In the day that thou eatest thereof, thou shalt surely die. Gen. ii. 17.

If my debtors do not keep their day, . . . I must with patience all the terms attend. Dryden.

4Sense 4. Day of battle; hence, successful combat or contest; victory.

His name struck fear, his conduct won the day. Roscommon.

Astronomical day, the same as the true solar day, beginning at the instant the sun’s center is on the meridian of the place, its 24 hours being numbered from 1 to 24; also, the sidereal day, as that most used by astronomers.—But or only from day to day, without certainty of continuance; temporarily. Bacon.—Civil day, the mean solar day, used in the ordinary reckoning of time, and among most modern nations beginning at mean midnight; its 24 hours are numbered in two series, each from 1 to 12. The Babylonians and Hindoos began their day at sun-rise, the Jews at sun-setting, the ancient Egyptians at midnight.—Day by day, daily; every day; continually; without intermission of a day. “Day by day we magnify thee.” 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 grace. (a.) (O. Eng. Law.) Three days beyond the return day in the writ for the party summoned to make his appearance; days granted by the court for delay. (b.) (Mercantile Law.) Days allowed by law or custom, usually three, for the payment of a note or bill of exchange, after the specified day of payment; a note or bill due on the seventh of the month thus being payable on the tenth. Kent. Story.—Day’s work (Naut.), the account or reckoning of a ship’s course for twenty-four hours, from noon to noon.—Mean solar day (Astron.), the mean or average of all the apparent solar days of the year.—One day, or one of these days, at a particular time, usually of the future, rarely of the past; sooner or later. “Well, niece, I hope one day to see you fitted with a husband.” Shak.—To-day, on the present day; this day; or at the present time.