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day (dā)
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n.
1. The period of light between dawn and nightfall; the interval from sunrise to sunset.
2.
a. The 24-hour period during which the earth completes one rotation on its axis, traditionally measured from midnight to midnight.
b. The period during which a celestial body makes a similar rotation.
3. One of the numbered 24-hour periods into which a week, month, or year is divided.
4. The portion of a 24-hour period that is devoted to work, school, or business: an eight-hour day; a sale that lasted for three days.
5. A 24-hour period or a portion of it that is reserved for a certain activity: a day of rest.
6.
a. A specific, characteristic period in one's lifetime: In Grandmother's day, skirts were long.
b. A period of opportunity or prominence: Every defendant is entitled to a day in court. That child will have her day.
7. A period of time in history; an era: We studied the tactics used in Napoleon's day. The day of computer science is well upon us.
8. days Period of life or activity: The sick cat's days will soon be over.
adj.
1. Of or relating to the day.
2. Working during the day: the day nurse.
3. Occurring before nightfall: a day hike.
Idioms:
day after day
For many days; continuously.
day in, day out
Every day without fail; continuously.
one day
Someday.
one of these days
Someday.
one of those days
A difficult or trying day.
these days
At present; nowadays.

[Middle English dai, day, from Old English dæg; see agh- in the Appendix of Indo-European roots.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Day or Daye (dā), Stephen 1594?-1668.
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English-born colonist who was the first printer in New England. His Bay Psalm Book appeared in 1640.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Day, Dorothy 1897-1980.
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American journalist and reformer who cofounded the Catholic Worker in 1933 to promote pacifism and social justice.
(click for a larger image)
Dorothy Day

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Day (dā), Clarence Shepard, Jr. 1874-1935.
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American writer best known for his autobiographical Life with Father (1935) and Life with Mother (published 1937).

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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