English explanatory dictionary online >> sun

Results for: sun



sun  (sn)
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
To expose to the suns rays, as for warming, drying, or tanning.
To expose oneself or itself to the sun.
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.]
cutaway of the sun

sun [sʌn]
1. (Astronomy) the star at the centre of our solar system. It is a gaseous body having a highly compressed core, in which energy is generated by thermonuclear reactions (at about 15 million kelvins), surrounded by less dense radiative and convective zones serving to transport the energy to the surface (the photosphere). The atmospheric layers (the chromosphere and corona) are normally invisible except during a total eclipse. Mass and diameter: 333 000 and 109 times that of earth respectively; mean distance from earth: 149.6 million km (1 astronomical unit) Related adj solar
2. (Astronomy) any star around which a planetary system revolves
3. (Earth Sciences / Physical Geography) the sun as it appears at a particular time or place the winter sun
4. (Physics / General Physics) the radiant energy, esp heat and light, received from the sun; sunshine
5. a person or thing considered as a source of radiant warmth, glory, etc.
6. (History / Heraldry) a pictorial representation of the sun, often depicted with a human face
7. (Literature / Poetry) Poetic a year or a day
8. (Literature / Poetry) Poetic a climate
9. Archaic sunrise or sunset (esp in the phrase from sun to sun)
(Medicine / Pathology)
catch the sun to become slightly sunburnt
place in the sun a prominent or favourable position
(Transport / Nautical Terms)
take or shoot the sun Nautical to measure the altitude of the sun in order to determine latitude
(Medicine / Pathology)
touch of the sun slight sunstroke
under or beneath the sun on earth; at all nobody under the sun eats more than you do
vb suns, sunning, sunned
1. (Life Sciences & Allied Applications / Physiology) to expose (oneself) to the sunshine
2. (Life Sciences & Allied Applications / Physiology) (tr) to expose to the sunshine in order to warm, tan, etc.
[Old English sunne; related to Old High German sunna, Old Frisian senne, Gothic sunno]
sunlike  adj

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 Suns plasma. The Suns surface temperature (at its photosphere) is approximately 6,200 degrees C (11,200 degrees F). Turbulent surface phenomena analogous to the Earths 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.
cutaway of the Sun

sun  /sn/  n. 1 [C] the star around which the Earth and other planets revolve and draw light, heat, and energy: The sun rises every morning and sets every evening. 2 [U] the heat and light of the sun: Have fun at the beach, but dont get too much sun.
v. [I;T] sunned, sunning, suns to bathe in the sunlight: She loved to sun herself on the beach. sun

Enter word: