day

Noun

day (plural days)

1. The time when the Sun is above the horizon and it lights the sky.
   • day and night; I work at night and sleep during the day.
   • The day was cool and snappy for August, and the Rise all green with a lavish nature. Now we plunged into a deep shade with the boughs lacing each other overhead, and crossed dainty, rustic bridges over the cold trout-streams,[…].1897 December (indicated as 1898), Winston Churchill, chapter VIII, in The Celebrity: An Episode, New York, N.Y.: The Macmillan Company; London: Macmillan & Co., Ltd., →OCLC

   Synonyms:

   daylight, daylength, daytime, photoperiod

   Antonyms:

   night, nightertale, nighttide, nighttime, scotoperiod, skotoperiod

2. A period of time equal or almost equal to a full day-night cycle, being 24 hours long.
   • Holonyms: week < megasecond < fortnight < month < year < gigasecond < century < kiloannum, kiloyear, millennium < terasecond < mega-annum, megayear < petasecond < giga-annum, gigayear < exasecond < zettasecond < yottasecond < ronnasecond < quettasecond
   • Meronyms: quectosecond < rontosecond < yoctosecond < zeptosecond < attosecond < femtosecond < picosecond < nanosecond < microsecond < millisecond < centisecond < decisecond < second < decasecond < minute < hectosecond < kilosecond < hour

   Synonyms:

   twenty-four hour day, 24-hour day, nychthemeron

   1. The time taken for the Sun to seem to be in the same place in the sky twice; a solar day.
   2. The time taken for the Earth to make a full rotation about its axis with respect to the fixed stars; a sidereal day or stellar day.
3. (informal) A 24-hour period beginning at 6am or sunrise.
   • Your 8am forecast: The high for the day will be 30 and the low, before dawn, will be 10.
4. A period of time between two set times which mark the beginning and the end of day in a calendar, such as from midnight to the following midnight or (Judaism) from nightfall to the following nightfall.
   • The day begins at midnight.
   • Monday is the first day of the week in many countries of the world.
5. The rotational period of a planet.
   • A day on Mars is slightly over 24 hours.
   • Radio emissions indicate that a Neptunian day lasts 16.1 hours, an hour and a half shorter than previously thought.1990 August, Rick Gore, “Neptune: Voyager's Last Picture Show”, in National Geographic, volume 178, number 2, page 39
6. The part of a day period which one spends at one’s job, school, etc.
   • I worked two days last week.
   • “[…]if you call my duds a ‘livery’ again there'll be trouble. It's bad enough to go around togged out like a life saver on a drill day, but I can stand that 'cause I'm paid for it. What I won't stand is to have them togs called a livery.[…]”1913, Joseph C[rosby] Lincoln, chapter VII, in Mr. Pratt’s Patients, New York, N.Y.; London: D[aniel] Appleton and Company, →OCLC
7. An observance lasting for a day, such as an annual holiday.
   • Christmas Day
   • Remembrance Day
8. A day set aside for a specified activity.
   • leg day, moving day, observation day
9. A specified time or period; time, considered with reference to the existence or prominence of a person or thing; age; time; era.
   • every dog has its day; in that day; back in the day; in those days
   • This new-comer was a man who in any company would have seemed striking.[…]Indeed, all his features were in large mold, like the man himself, as though he had come from a day when skin garments made the proper garb of men.1910, Emerson Hough, chapter I, in The Purchase Price: Or The Cause of Compromise, Indianapolis, Ind.: The Bobbs-Merrill Company, →OCLC

   Synonyms:

   era, epoch, age, cycle, generation, Great Year, interval, period, Platonic year, time

10. A period of contention of a day or less.
    • The day belonged to the Allies.

Verb

day (third-person singular simple present days, present participle daying, simple past and past participle dayed)

1. (intransitive, rare) To spend a day (in a place).
   • I nighted and dayed in Damascus town[.]1885, Richard F. Burton, chapter XXIII, in The Book of the Thousand Nights and a Night, volume I, The Burton Club, page 233

Proper noun (1) capitalized: Day

IPA/deɪ/

Day

1. A surname originating as a patronymic derived from a medieval diminutive of David.
2. An English surname originating as an occupation from day as a word for a "day-servant", an archaic term for a day-laborer, or from given names such as Dagr, Daug, Dege, and Dey, cognate with Scandinavian Dag.
3. A surname from Irish can be found as both Day and O'Day from Ó Deághaidh (“descendant of a person named Good Luck”).
4. An unincorporated community in Modoc County, California.
5. A census-designated place and unincorporated community in Lafayette County, Florida.
6. A township in Montcalm County, Michigan.
7. An unincorporated community in Isanti County, Minnesota.
8. An unincorporated community in Taney County, Missouri.
9. A town in Saratoga County, New York.
10. A town in Marathon County, Wisconsin.

Proper noun (2) capitalized: Day

Day

1. A Mbum-Day language of Chad.