Definition of orbit in English:



  • 1The curved path of a celestial object or spacecraft around a star, planet, or moon, especially a periodic elliptical revolution.

    • ‘No, they did find one recently that had a Jupiter-like planet in a Jupiter-like orbit around a Sun-like star, that's the closest they've come so far.’
    • ‘No photograph can prepare you for this, no understanding of orbits and celestial mechanics.’
    • ‘For a planet in an Earth-sized orbit, it will only be in front of its star for a few hours, once every year.’
    • ‘These planets have circular orbits similar to the orbits of planets in our solar system.’
    • ‘This creates increased atmospheric drag on spacecraft in low orbits, shortening their orbital lifetime.’
    • ‘They also know that orbits of planets are elliptical and not circular, which of course is another advanced bit of information.’
    • ‘Will they build up into still broader disarray and eventually move our planet out of its orbit around the sun?’
    • ‘The concern is that the gravitational tug of Jupiter could alter the orbit of the spacecraft and cause it to hit Europa or another moon.’
    • ‘Similarly, Kepler's discovery of the elliptical orbit of the planets did not sit well with the religious establishment.’
    • ‘He therefore accepted Kepler's theory of elliptical orbits for the planets and tested Kepler's laws by direct observation.’
    • ‘Schwabe had been looking at the Sun to discover a planet inside the orbit of Mercury.’
    • ‘Mars is an average of 48 million miles from Earth, though the distance can vary greatly depending on where the two planets are in their orbits around the sun.’
    • ‘The few planets maintain their orbits with great regularity, and we can make very good predictions where they will be at some time in the future.’
    • ‘A planet or asteroid in the solar system follows an elliptical orbit, with the sun at one focus.’
    • ‘Of course our model above is very simplified: there are more than just two massive bodies in the solar system, the planets' orbits are elliptical rather than circular, and there are other forces at work, not just gravity.’
    • ‘The planets are in orbits around the sun which are almost circular.’
    • ‘This will put the spacecraft into an orbit that is less than 200 miles above the surface.’
    • ‘Those objects that pose a threat will have their orbits altered by spacecraft made on the Moon.’
    • ‘Today we know it is gravity that holds the planets and stars in their orbits making them appears to be hung on nothing.’
    • ‘Most planets still had regular orbits, and cycles of days, months, and years.’
    course, path, circuit, track, trajectory, rotation, revolution, circle, cycle, round
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    1. 1.1One complete circuit around an orbited body.
      • ‘The further a planet lies from its star, the longer it takes to complete an orbit and the longer astronomers have to observe to detect it.’
      • ‘The Soviet Union in 1959 was the first country to complete a moon orbit.’
      • ‘The new Hubble findings close a decade of speculation and debate as to the true nature of this ancient world, which takes a century to complete each orbit.’
      • ‘This means that after eight of our orbits Venus has circuited the Sun 13 times, and returns to more or less the same position relative to us.’
      • ‘The craft itself remained in orbit for nearly six months, and completed 1400 orbits of the Earth.’
      • ‘The Moon crosses the plane of Earth's orbit twice in each complete orbit.’
      • ‘As it moves further away from us, the Moon takes longer to complete an orbit.’
      • ‘Jupiter takes 12 years to complete one orbit around the Sun.’
      • ‘It completes its tight orbit in less than 10 days, compared to the 365 required for our year.’
      • ‘One was spotted by the Europeans and is so close to its parent star that it completes an orbit in just four days.’
      • ‘At these higher orbits it can take many hours to complete a single orbit.’
      • ‘Shenzhou I completed fourteen orbits and returned to earth after just twenty-one hours, but even so it achieved a big step forward for the Chinese.’
      • ‘Saturn takes approximately 27 years to complete its orbit.’
      • ‘The object will probably complete six orbits around Earth before returning to a solar orbit next summer, Chodas says.’
      • ‘Jupiter takes about 12 years to complete its orbit but Zu was able to give a much more accurate value than that.’
      • ‘During 6 of the 16 daily orbits, the Foton spacecraft will be in a suitable orbital position for Kiruna to receive signals from it.’
      • ‘As Kepler had pointed out, objects in low orbits will complete an orbit around the earth faster than those in high orbits, even though their linear velocity is lower.’
      • ‘Yang's trip lasted more than twenty-one hours and took him on fourteen orbits around the Earth.’
      • ‘The capsule is expected to remain in orbit for 14 orbits and 21 hours before re-entry and a parachute landing in inner Mongolia.’
      • ‘The vessel made a small orbit round the moon before launching itself into space at reasonable speeds.’
      lap, turn, tour, round, circle, revolution, loop
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    2. 1.2The state of being on or moving in an orbit.
      ‘planets in orbit around the sun’
      • ‘During its final years in orbit, the Russian space station Mir suffered a number of mishaps.’
      • ‘The stations could not be resupplied, so they had limited lifetimes in orbit.’
      • ‘The Russians had the space station Mir in orbit and American astronauts were on board for lengthy visits.’
      • ‘However, a propellant-free way of moving objects around in orbit very slowly is under development.’
      • ‘Integrating spacecraft is not an easy task, and it is easier to do it on the ground than in orbit.’
      • ‘The most interesting problem would have been refueling the booster in orbit.’
      • ‘Galileo has operated in orbit more than three times longer than its originally planned mission.’
      • ‘Cryosat, which is slated to launch on 8 October, will spend three years in orbit, studying the polar caps, the BBC reports.’
      • ‘During its nearly 14 years in orbit, Hubble has proven to be one of the most significant and successful scientific instruments in its time.’
      • ‘A vehicle in orbit is less provocative than one flying through territorial airspace.’
      • ‘Cassini is safely in orbit around Saturn, and the pictures and data are flooding in.’
      • ‘Two space probes are already in orbit around Mars: Global Surveyor and Odyssey.’
      • ‘To help us understand these events, we compare data from Odyssey to data from similar instruments in orbit around Earth.’
      • ‘Cassini, however, remains in orbit around Saturn and is designed to function for another four years.’
      • ‘Human-made space debris in orbit around Earth is commonly called orbital debris.’
      • ‘Remember Cassini, the multibillion dollar spaceship we put in orbit around Saturn back in July?’
      • ‘It will spend four years in orbit around the gas giant, exploring the planet and its rings and moons.’
      • ‘The Hubble space telescope has been in orbit for 15 years, during which time it has taken over 750,000 images of the universe.’
      • ‘Its seven scientific instruments will collect data for a full year in orbit around Mercury, an average 58 million kilometres from the sun.’
      • ‘The shuttle era also witnessed the first untethered space walks by U.S. astronauts in orbit.’
    3. 1.3The path of an electron around an atomic nucleus.
      • ‘The electrons are released at this temperature and they are able to return to their normal atomic orbits.’
      • ‘For many atoms, the combinations of electrons in their orbits cancel each other out.’
      • ‘Rydberg atoms do not move or collide because they are laser cooled, but the electron orbits of adjacent atoms can overlap.’
      • ‘The electrons do have different discrete energies, but they do not follow circular orbits.’
      • ‘In its excited state, an electron in the molecule is pushed into a higher atomic orbit.’
      • ‘Scientists used to believe that electrons circled around the nucleus in planet-like orbits.’
      • ‘The more radical physicists suspected that problems arose not from the particular models employed, but from fundamental classical assumptions that electrons moved in determinate orbits.’
      • ‘Quarks are bound together by the strong nuclear force to form protons and neutrons in atomic nuclei, while the electromagnetic force holds electrons in orbits around the nucleus.’
      • ‘Third, the size of the hydrogen atom's first electron orbit is accurately predicted.’
      • ‘This is the process in which a proton is converted into a neutron by the nucleus capturing a negative electron from one of the inner orbits of its atom.’
      • ‘A classical physicist would have supposed that electrons encircling a nucleus could do so in orbits whose radii could take any value.’
      • ‘Atoms give up excess internal energy by giving off photons as electrons return to lower energy orbits.’
      • ‘The size of the atom is defined not by hard boundaries but by how far the electron orbits reach.’
      • ‘I know I've read about electrons shifting orbits quite a bit before, but I'm too foggy to think of where and how right now.’
      • ‘Electrons are thus ‘spread out’ quite a bit in their orbits about the nucleus.’
      • ‘Each electron orbit of the same size or energy could only hold so many electrons.’
      • ‘For example, an electron can exist simultaneously in different orbits (a fact which is responsible for giving us the laws of chemistry).’
      • ‘The maximum number of electrons in any orbit is fixed.’
      • ‘The researchers successfully recorded an interval of one ten million billionth of a second: that's shorter than the period of an electron's orbit in a hydrogen atom.’
      • ‘Flying subatomic particles collide with other atoms in their path, knocking electrons out of their orbits.’
  • 2A sphere of activity, interest, or application.

    ‘a radical filmmaker outside the Hollywood orbit’
    • ‘In the 1980s and 90s, the emergence of centers within the orbit of the seminary has accented new mission challenges.’
    • ‘He claims that liberal opinions on these matters fall within the orbit of evangelical Christianity, but makes very little reference to recent books that refute these false notions.’
    • ‘The difficulty is in making the concept both concrete and yet expansive enough to include everyone who ought to fall within our orbit of concern.’
    • ‘The southern parts are within the orbit of London and discharge commuters into Euston, St Pancras, King's Cross, and Liverpool Street.’
    • ‘Second, it is symptomatic that purposeful Baptist theological reflection has emerged outside the Baptist orbit.’
    • ‘I do not think there is one person within his orbit who was not the beneficiary of his wisdom, encouragement, and generosity.’
    • ‘In a different orbit altogether are forthcoming books by two authors also associated with the pop business.’
    • ‘It may be moving closer to the orbit of Western Europe, but there are still enormous obstacles to overcome.’
    • ‘It places any criticism of government policy in the orbit of illegal activity.’
    • ‘The book opens with cosmopolitan collecting activities of noble families in the orbit of the Russian court.’
    • ‘Affable by nature, Wallace moves from the stage to the bar and back again, using words of thanks and admiration to chat up everyone within his orbit.’
    • ‘It should not be concluded from this that Norman and Plantagenet kings were reluctant to see the orbit of their influence enlarged.’
    • ‘In fact, this sense of daring separates him from many creative artists, both within the Hollywood sphere and the indie orbit.’
    • ‘What the high court has done, however, is to at least bring the torturers within the orbit of the law, subject to some form of accountability and judicial restraint.’
    • ‘The best known Marxist economists outside the orbit of official Communism found it all but impossible to come to terms with what was happening.’
    • ‘Commenting on the polls is not within the orbit of this bill.’
    • ‘Nunney is within commuting distance of Bath and Bristol and within the orbit of Londoners seeking weekend retreats.’
    • ‘To direct one's thoughts against someone is to remain within their orbit.’
    • ‘He may have come within the orbit of the literary set of which Jonson had been the leader.’
    • ‘She appeared to be one of these people who think they know everything worth knowing, and who deem it their duty to enlighten all who come within their orbit.’
    sphere, sphere of influence, area of activity, range, reach, scope, ambit, compass, sweep, jurisdiction, authority, remit, span of control, domain, realm, province, territory, preserve, department, turf
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  • 3Anatomy
    The cavity in the skull of a vertebrate that contains the eye; the eye socket.

    • ‘The orbit is a socket for the eyeball, muscles, nerves, and vessels that are necessary for proper functioning of the eye.’
    • ‘The major reptile groups are classified according to the pattern of openings in the skull roof behind the orbits.’
    • ‘The needle is directed upward and laterally to avoid passing through the foramen into the orbit.’
    • ‘Because the orbit (eye socket) is made of bone it cannot expand to accommodate the protruding eyeball.’
    • ‘Orbital inflammation is often caused by sinus infection because of the multiple venous channels that exists between the sinuses and orbits.’
    1. 3.1The area around the eye of a bird or other animal.
      • ‘The scales vary in form and size from the orbit, head, gill-covers, fins and trunk areas.’
      • ‘The margins of the orbits are raised above the general surface of the skull.’


  • 1 (of a celestial object or spacecraft) move in orbit around (a star, planet, or moon)

    ‘Mercury orbits the Sun’
    • ‘The public has an unprecedented opportunity to suggest places on Mars that should be photographed from a spacecraft orbiting that planet.’
    • ‘Second, it is the only planet currently known to orbit a binary star system.’
    • ‘If successful, the van-sized spacecraft will orbit the planet 640 km over our heads.’
    • ‘Yoder's group made the bulge measurements by monitoring the motion of the Mars Global Surveyor spacecraft as it orbited the planet over the past 3 years.’
    • ‘For example, currently, many scientists are searching for planets orbiting other stars.’
    • ‘He said thinking of space in those terms amounts to revolution comparable to Copernicus's proof of a solar system that orbited the sun.’
    • ‘Sedna, the mysterious minor planet orbiting the Sun beyond the far edge of the Kuiper Belt, is gradually yielding its secrets to planetary scientists.’
    • ‘This newly discovered planet orbits a star called Tau Gruis, which is about 100 light-years away.’
    • ‘Titan is slightly bigger than the planet Mercury, and is only called a moon because it orbits the giant planet Saturn rather than the Sun.’
    • ‘Like planets, comets orbit the Sun, but their path is usually long and narrow.’
    • ‘During just the last few years of the twentieth century, astronomers began to find planets orbiting other stars.’
    • ‘Simply provide us with the exact mass, orbital speed and orbital distance of an undiscovered gas giant planet orbiting a star near our solar system.’
    • ‘Probes that orbit the planet have studied Mars and some spacecraft have even landed on it.’
    • ‘They detected a new planet orbiting a distant star called 51 Pegasi.’
    • ‘Four years later the Clementine spacecraft orbited the Moon, and NASA's Lunar Prospector mission followed in 1998.’
    • ‘If all goes well, Messenger will be the first spacecraft to orbit that planet.’
    • ‘Nasa astronomers said they had found the smallest planets yet orbiting stars beyond our Sun.’
    • ‘In 1994, the SDI-NASA Clementine spacecraft orbited the Moon and mapped its surface.’
    • ‘We have one great thing in common with Mars - both planets orbit the same star.’
    • ‘After astronomers find a planet orbiting a given star, they continue to monitor that star in the hope of detecting additional planets.’
    1. 1.1[no object]Fly or move around in a circle.
      ‘the mobile's disks spun and orbited slowly’
      • ‘Another Texan flown by Mike McCrae orbited around the formation so a press photographer could record the event.’
      • ‘We continued to orbit until our two remaining wingmen joined.’
      • ‘On the floor and roof several other, albeit smaller, structures orbited around the larger one.’
      • ‘So, flight planners must schedule the takeoff for a precise interval when the station is orbiting directly overhead.’
      • ‘We orbited and were tasked to broaden our search for more contacts.’
      • ‘Vast quantities can be locked up inside the rocky interior of a planet, or sloshing away under the permanently icebound exterior of a world orbiting far from an external source of heat.’
      • ‘As it orbits, LOLA will send out laser pulses 28 times per second.’
      • ‘A work-in-progress orbiting about 250 miles above Earth, the ISS will eventually carry more than an acre's worth of solar panels.’
      • ‘It was reported that the Privateer was orbiting with a C - 54, waiting to be called in by a lead aircraft to drop retardant on the Big Elk fire.’
      • ‘While my copilot coordinated our recovery, I lazily orbited over the rocks.’
      • ‘My father and I stopped walking, and he orbited slowly until he faced us.’
      • ‘It orbits very close to its star, about one-fiftieth the distance between the Earth and the sun.’
      • ‘It's like launching from 100 miles south of New Orleans, flying to Chicago, orbiting over the Great Lakes and waiting for the call on station.’
      • ‘They took the B - 25 up to 2000 feet and orbited over Chino for 20 minutes before landing.’
      • ‘We were stationed 21,000 feet and orbited while looking for surface tracks around the battlegroup.’
      • ‘Because it orbits above the atmosphere, which both smears light and blocks out major portions of the spectrum, Hubble can see things that no ground-based telescope will ever see.’
      • ‘We were orbiting and waiting for our intended target - a B - 17G Flying Fortress.’
      • ‘In the extreme distance, an object that appeared little more than a white blur orbited slowly.’
      • ‘George Hulett and myself were orbiting over the desert at 5500 feet in the Bonanza camera plane when Bruce Lockwood streaked past us, the bright red nose of the Yak 3 a blur.’
      • ‘Both aircraft orbited over the water while we figured out what to do.’
      revolve round, circle round, go round, travel round
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    2. 1.2Put (a satellite) into orbit.
      • ‘If the Soviets could orbit Sputnik, who was to say that they were not proceeding to develop the capability for a space-based missile attack?’
      • ‘Militaries that can not afford communications satellites of their own can lease transponders on the satellites orbited by other countries, and some - like Australia - have already done so.’


  • into orbit

    • informal Into a state of heightened performance, activity, anger, or excitement.

      ‘his goal sent the fans into orbit’
      • ‘The noise had sent the stadium into orbit and Dublin just needed another score or two to fix Tyrone with a stare and make them think that losing was a possibility.’
      • ‘Any compliment she would give him in the past would send him into orbit.’
      • ‘If you are an aficionado of Spanish wines, the list here will send you into orbit.’
      • ‘We just about went into orbit when they came up with a better figure than ours.’


Mid 16th century ( orbit): from Latin orbita course, track (in medieval Latin eye socket), feminine of orbitus circular from orbis ring.