daylight saving time

(redirected from Daylight time)
Also found in: Dictionary, Thesaurus.

daylight saving time

(DST), time observed when clocks and other timepieces are set ahead so that the sun will rise and set later in the day as measured by civil timecivil time,
local time based on universal time. Civil time may be formally defined as mean solar time plus 12 hr; the civil day begins at midnight, while the mean solar day begins at noon.
..... Click the link for more information.
. The amount of daylight on a given dayday,
period of time for the earth to rotate once on its axis. The ordinary day, or solar day, is measured relative to the sun, being the time between successive passages of the sun over a stationary observer's celestial meridian.
..... Click the link for more information.
 of the year at a given latitude is fixed, but over the year the hours of sunrise and sunset vary from day to day. During the summer months, the sun rises earlier and sets later and there are more hours of daylight. If clocks and other timepieces are set ahead in the spring by some amount (usually one hour), the sun will rise and set later in the day as measured by those clocks. This provides more usable hours of daylight for activities that occur in the afternoon and evening, such as outdoor recreation. Daylight saving time can also be a means of conserving electrical and other forms of energy. In the fall, as the period of daylight grows shorter, clocks are set back to correspond to standard timestandard time,
civil time used within a given time zone. The earth is divided into 24 time zones, each of which is about 15° of longitude wide and corresponds to one hour of time. Within a zone all civil clocks are set to the same local solar time.
..... Click the link for more information.
.

Benjamin Franklin, when serving as U.S. minister to France, wrote an article recommending earlier opening and closing of shops to save the cost of lighting. In England, William Willett in 1907 began to urge the adoption of daylight saving time. During World War I the plan was adopted in England, Germany, France, and many other countries. In the United States, Robert Garland of Pittsburgh was a leading influence in securing the introduction and passage of a law (signed by President Wilson on Mar. 31, 1918) establishing daylight saving time in the United States. After World War I the law was repealed (1919). In World War II, however, national daylight saving time was reestablished by law on a year-round basis. National year-round daylight saving time was adopted as a fuel-saving measure during the energy crisis of the winter of 1973–74. In late 1974, standard time was reinstituted for the winter period. In 1987 federal legislation fixed the period of daylight saving time in the United States as the first Sunday (previously the last Sunday) in April to the last Sunday in October; it was expanded in 2005 (effective 2007) to extend from the second Sunday in March to the first Sunday in November. Arizona and Hawaii do not use daylight saving time.

daylight saving time

[¦dā‚līt ‚sāv·iŋ ‚tīm]
(astronomy)
A variation of zone time, usually 1 hour more advanced than standard time, frequently kept during the summer to make better use of daylight. Also known as summer time.
References in periodicals archive ?
Under the proposal, daylight time would last through the first week in November and would start after the first week in March.
Oregonians passed an initiative in 1952 establishing standard time statewide, but some communities stuck with daylight time. In 1962, the Legislature referred a measure to the ballot establishing daylight saving time.
eastern daylight time. This broadcast, produced jointly by CDC and the Agency for Toxic Substances and Disease Registry, will provide an overview of GIS applications in public health, environmental health, and health-care practice, including research and surveillance using GIS.
At 4.20am Pacific Daylight Time on Friday August 6 1999, eBay Inc's servers crashed for the fifth time since June 10.
Eastern Daylight TIme (EDT) today, August 13, 2019 -- 9:00 p.m.
Eastern Daylight Time (EDT); RBC Capital Markets Automotive, Industrials and Transportation Conference, Toronto, ON on May 15, 2019 starting at 3:50 p.m.
Central Daylight Time -which I independently confirmed with a rather unusual method.
This open season will commence on 8 April 2016 at 8:00 Central Daylight Time and will close on 9 May 2016 at 17:00 Central Daylight Time.
The Pacific Tsunami Warning Centre (PTWC) issued its warning and watch alerts for areas in the South Pacific after the quake struck at 1212 AEDT (Australian Eastern Daylight Time,) on Wednesday, but cancelled at around 1450 AEDT.
Additionally, the meeting will begin at 11:00 Pacific Daylight Time at the company's headquarters at 302 Enzo Drive, San Jose, California 95138 and all stockholders of record as of the close of business on 27 March 2012 are eligible to vote at the meeting.
Mountain Daylight Time. A spokeswoman for Denver Health Medical Center said more than 20 people had been taken to Denver area hospitals.
These fares are available to purchase until midnight (Pacific Daylight time) on Thursday for travel between 2 November and 20 December 2009 and between 24 December and 28 March 2010.