sun

sun  (sn) n. 1. often Sun A star that is the basis of the solar system and that sustains life on Earth, being the source of heat and light. It has a mean distance from Earth of about 150 million kilometers (93 million miles) a diameter of approximately 1,390,000 kilometers (864,000 miles) and a mass about 330,000 times that of Earth. 2. A star that is the center of a planetary system. 3. The radiant energy, especially heat and visible light, emitted by the sun; sunshine. 4. A sunlike object, representation, or design. v. sunned, sun·ning, suns v.tr. To expose to the sun's rays, as for warming, drying, or tanning. v.intr. To expose oneself or itself to the sun. Idioms: in the sun In the public eye. under the sun On the earth; in the world. [Middle English, from Old English sunne; see swel- in Indo-European roots.]

sun cutaway of the sun

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sun

Noun

1. the star that is the source of heat and light for the planets in the solar system Related adjective solar

2. any star around which a system of planets revolves

3. the heat and light received from the sun; sunshine

4. catch the sun to become slightly suntanned

5. under the sun on earth; at all: there are no free lunches under the sun

Verb

[sunning, sunned]

sun oneself to lie, sit, or walk in the sunshine on a warm day [Old English sunne]

sunless adj

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sun  (sn) Often Sun. A medium-sized, main-sequence star located in a spiral arm of the Milky Way galaxy, orbited by all of the planets and other bodies in our solar system and supplying the heat and light that sustain life on Earth. Its diameter is approximately 1.4 million km (868,000 mi), and its mass, about 330,000 times that of Earth, comprises more than 99 percent of the matter in the solar system. It has a temperature of some 16 million degrees C (27 million degrees F) at its core, where nuclear fusion produces tremendous amounts of energy, mainly through the series of reactions known as the proton-proton chain. The energy generated in the core radiates through a radiation zone to an opaque convection zone, where it rises to the surface through convection currents of the Sun's plasma. The Sun's surface temperature (at its photosphere) is approximately 6,200 degrees C (11,200 degrees F). Turbulent surface phenomena analogous to the Earth's weather are prevalent, including magnetic storms, sunspots, and solar flares. The Sun was formed along with the rest of the solar system about 4.5 billion years ago and is expected to run out of its current hydrogen fuel in another 5 billion years, at which point it will develop into a red giant and ultimately into a white dwarf. See Table at solar system. See Note at dwarf star.

sun cutaway of the Sun

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Sun

See also astronomy; climate; cosmology; equator; light; planets; weather.

celidography

Archaic. a description of the surface markings on a planet or the spots on the sun.

coronagraphy

the observation of the corona of the sun by use of a telescope modifled to simulate an eclipse. — coronagraphic, adj.

heliodon

an instrument used in astronomy to show the apparent movement of the sun.

heliography

1. the measurement of the duration and intensity of sunlight.
2. the system or process of signaling by reflecting the sun’s rays in a mirror.
3. an early photographic process involving coated metal plates exposed to sunlight. — heliographer, n. — heliographic, heliographical, adj.

heliolatry

the worship of the sun. — heliolator, n.

heliology

Archaic. the science of the sun. — heliologist, n.

heliomania

an abnormal love of the sun.

heliophobia

1. an abnormal fear of sunlight.
2. an avoidance of sunlight.

helioseismology

the study of motions of the solar surf ace.

heliotherapy

a method of treating illness by exposure to the rays of the sun.

pyrheliometer

an instrument for measuring the intensity of the sun’s radiation. — pyrheliometric, adj.

radiometer

an instrument for measuring the intensity of radiant energy, composed of vanes which rotate at speeds proportionate to the intensity of the energy source. — radiometric, adj.

radiometry

the measurement of radiant energy by means of a radiometer. — radiometric, adj.

radiophony

the transformation of radiant energy into sound.

siriasis

1. sunstroke.
2. Obsolete, a sun bath or exposure to the sun for curative purposes.

solarism

1. the explanation of myths by reference to the sun or the personifi-cation of the sun, as the hero as sunfigure.
2. an overreliance on this method of interpretation. — solarist, n.

solarium

a room designed and situated so as to receive the maximum amount of sunlight.

Thesaurus

Noun	1.	Sun - the star that is the source of light and heat for the planets in the solar system; "the sun contains 99.85% of the mass in the solar system"; "the Earth revolves around the Sun" chromosphere - a gaseous layer of the sun's atmosphere (extending from the photosphere to the corona) that is visible during a total eclipse of the sun photosphere - the intensely luminous surface of a star (especially the sun) solar system - the sun with the celestial bodies that revolve around it in its gravitational field
	2.	sun - the rays of the sun; "the shingles were weathered by the sun and wind" sunlight, sunshine light, visible light, visible radiation - (physics) electromagnetic radiation that can produce a visual sensation; "the light was filtered through a soft glass window" sunburst - a sudden emergence of the sun from behind clouds sunbeam, sunray - a ray of sunlight
	3.	sun - a person considered as a source of warmth or energy or glory etc important person, influential person, personage - a person whose actions and opinions strongly influence the course of events
	4.	sun - any star around which a planetary system revolves star - (astronomy) a celestial body of hot gases that radiates energy derived from thermonuclear reactions in the interior
	5.	Sun - first day of the week; observed as a day of rest and worship by most Christians Dominicus, Lord's Day, Sunday day of rest, rest day - a day set aside for rest weekend - a time period usually extending from Friday night through Sunday; more loosely defined as any period of successive days including one and only one Sunday
Verb	1.	sun - expose one's body to the sun sunbathe lie - be lying, be prostrate; be in a horizontal position; "The sick man lay in bed all day"; "the books are lying on the shelf"
	2.	sun - expose to the rays of the sun or affect by exposure to the sun; "insolated paper may turn yellow and crumble"; "These herbs suffer when sunned" insolate, solarise, solarize expose - expose or make accessible to some action or influence; "Expose your students to art"; "expose the blanket to sunshine"

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sun

noun Sol, Roman myth Helios Greek myth Phoebus Greek myth daystar (poetic) eye of heaven, Phoebus Apollo Greek myth

sun yourself sunbathe, tan, bask >> adjective solar

Translations

sun [sʌn] n → sol m;

they have everything under the sun → no les falta nada, tienen de todo

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sun [sʌn] n → soleil m;

in the sun → au soleil;

to catch the sun → prendre le soleil;

everything under the sun → absolument tout

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sun [sʌn] n → Sonne f;

to catch the sun → einen Sonnenbrand bekommen;

everything under the sun → alles Mögliche

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sun [sʌn] n → sole m;

in the sun → al sole;

to catch the sun → prendere sole;

they have everything under the sun → hanno tutto ciò che possono desiderare