Definition of X-ray in US English:


(also x-ray, X ray)


  • 1An electromagnetic wave of high energy and very short wavelength, which is able to pass through many materials opaque to light.

    X-rays were formerly defined in terms of their wavelength, radiation of shorter wavelength than theirs being classed as gamma rays. They are now usually defined in terms of the mode of production: X-rays are produced by the deceleration of charged particles, especially electrons, or by electron transitions in atoms, while gamma rays arise from the radioactive decay of atomic nuclei

    • ‘Various kinds of radiation can be used: in order of increasing energy, electrons, X-rays, and gamma rays.’
    • ‘Most known radiation dangers occur at the high end of the electromagnetic spectrum, and include X-rays and gamma rays.’
    • ‘Ionizing radiation, which includes alpha particles, beta particles, gamma rays and X-rays, is radiation that has enough energy to knock an orbital electron off of an atom.’
    • ‘The jets contain relativistic winds that interact and collide, creating shock waves and emitting high-energy X-rays and gamma rays.’
    • ‘It was designed to study X-rays and gamma rays from solar flares.’
    • ‘Gamma rays and X-rays are two forms of ionizing radiation.’
    • ‘The radioactive material generates ionising radiations, which include alpha particles, beta particles, X-rays and gamma rays.’
    • ‘The same electron is just as capable of emitting X-rays, orange light, or radio waves - all that matters is the environment and interactions it finds itself in contact with.’
    • ‘Heating under controlled conditions or irradiating a mineral using X-rays, neutrons, gamma rays, or other energy sources will effect colour changes in many gems.’
    • ‘However, even this atmosphere is still too thin to protect us from the incoming radiation from space, such as ultraviolet light, X-rays and gamma rays, or charged particles such as protons and electrons.’
    • ‘Gamma rays are not particles but a form of electromagnetic radiation, like light, radio waves, and X-rays.’
    • ‘Gamma rays and X-rays lose energy in a variety of ways, but each involves liberating atomic electrons, which then deposit energy through interactions with other electrons.’
    • ‘In 1923, the American physicist Arthur Compton investigated the scattering of X-rays (high-frequency electromagnetic radiation) by matter.’
    • ‘Each color in this image represents a different region of the electromagnetic spectrum, from X-rays to infrared light.’
    • ‘Unlike exposure to external radiation sources such as cosmic rays or X-rays, radioactive nuclides are deposited within the body from food and water.’
    • ‘All the light that we see is made from electromagnetic waves, and so are infra-red and ultraviolet light, microwaves, radio waves and X-rays.’
    • ‘This means that energy that started out in the form of X-rays and gamma rays would now be in the form of microwaves, with wavelengths of around 1 millimeter or so.’
    • ‘The first magnetar candidates were a family of rare and peculiar galactic sources of gamma and X-rays called soft gamma repeaters (SGRs).’
    • ‘Rhessi shows us the high-energy radiation emitted by flares: their X-rays and gamma rays.’
    • ‘Fortunately for life on Earth, the atmosphere blocks out harmful, high-energy radiation like X-rays, gamma rays and most ultraviolet rays.’
    • ‘As X-rays pass through your body, different tissues absorb different amounts.’
    1. 1.1informal as modifier Denoting an apparent or supposed faculty for seeing beyond an outward form.
      ‘you didn't need X-ray eyes to know what was going on’
      • ‘I've also got X-ray vision, Super breath, and can leap four Range Rovers in a single bound.’
      • ‘Superman has X-ray vision: walls become permeable, transparent.’
      • ‘Television doctor Chris Steele has been given the all-clear from cancer after a ‘diagnosis’ from a Russian teenager who claims to have X-ray eyes.’
      • ‘The real nebula wouldn't look precisely like this, unless you have X-ray vision.’
  • 2A photographic or digital image of the internal composition of something, especially a part of the body, produced by X-rays being passed through it and being absorbed to different degrees by different materials.

    • ‘Moreover, Kodak's bets are paying off in health-imaging, where it's leveraging longstanding ties with doctors eager to replace X-rays with digital images.’
    • ‘Areas of blockage in the coronary artery show up on the X-ray images, so your doctor knows precisely where to target treatment.’
    • ‘In this procedure, a special contrast material is injected into one of your milk ducts before the X-ray images are taken.’
    • ‘Presumably a device based on this technology could provide full body X-rays of people at airports, something much more reassuring than a metal detector.’
    • ‘This one is a life-size body assembled from old X-rays.’
    • ‘Today, the most accurate expression of the Perfect Body is an X-ray.’
    • ‘The readers of the X-rays and the retinal photographs had no knowledge of the health of the subjects, that is they were not told about any diseases the subjects had.’
    • ‘Often used to identify fractures or tumors that may not be visible on an X-ray.’
    • ‘The York trust is already in the process of upgrading its switchboard to a system that works with computers so, using Internet technology, clinical images such as X-rays can be transmitted as well as phone calls.’
    • ‘Identification of Uday and Qusay's bodies was confirmed by X-rays, dental records and former Baath party officials who knew them.’
    • ‘I was even afraid to step off a curb because in my mind I kept seeing the image of the X-ray of my fractured fibula as I had seen it in the emergency room.’
    • ‘Currently, detection of breast cancer relies largely on radiologists reading X-rays known as mammograms.’
    • ‘Having the ability to analyze X-rays and scans digitally from a remote location can be extremely valuable.’
    • ‘It involves swallowing liquid, called barium, that shows up on the X-ray as it passes through your digestive system.’
    • ‘Most often, EMC points to images, e-mail, X-rays and medical records as the types of files meant to find their way onto a Centera.’
    • ‘Since the surgeon can feel with his fingers the position of the bones and the degree of correction, X-rays of the feet are not necessary except in complex cases.’
    • ‘From MRIs and X-rays to check images, broadcast content, and completed CAD / CAM designs, fixed content is an important class of data.’
    • ‘For example, most of the medical people at Parkland describe a big hole in the president's head in the rear or right rear, and yet the autopsy photographs and X-rays of the body don't show a big hole over here.’
    • ‘It also produces much more detailed images than X-rays because of its ability to separate different types of soft tissues.’
    • ‘‘The tumour was clearly visible in the original X-ray but the consultant missed it,’ said Paul.’
    radiogram, radiograph, x-ray image
    View synonyms
    1. 2.1 An act of photographing someone with an X-ray.
      ‘he will have an X-ray today’
      ‘would you send her for X-ray?’
      • ‘The doctor will take a history and perform a thorough physical exam, and may order a chest X-ray or blood tests to diagnose the condition.’
      • ‘Another casualty among the debris was Rangers' Chris Burke, who will go for an X-ray today after going over an ankle in the most innocuous circumstances.’
      • ‘Jason Maxwell was sent to hospital for X-rays after being carried off just minutes after scoring the equaliser against Barrow.’
      • ‘Your child's doctor may take X-rays or perform blood tests to exclude other conditions that can produce symptoms similar to those of JRA.’
      • ‘They will be in the hospital for a minimum of 10 to 14 days, getting IV antibiotics, multiple blood tests, X-rays, and probably a spinal tap.’
      • ‘And I returned to the GP as things seemed to get worse, and she did an X-ray and the radiologist and GP decided I had pneumonia.’
      • ‘After medical staff took X-rays and scanned its brain, the child was allowed to leave and appeared to be making satisfactory progress.’
      • ‘You may need X-rays or an ultrasound to check the kidneys and ureters.’
      • ‘The doctor may need to take several tests, including blood tests or X-rays, to diagnose your child.’
      • ‘Mrs Ferriby was transferred to the acute assessment unit where her blood pressure was reassessed, and an X-ray and blood tests were taken.’
      • ‘Chief Executive Steve Ferres said that Ramsden was having an X-ray on the injury today to assess the extent of the damage.’
      • ‘Ferguson claims it is too soon to say how badly injured Beckham is and the England skipper will have an X-ray in Manchester today but the player walked unaided on to the plane home.’
      • ‘If your injuries or condition is more serious, then you might be sent for an X-ray or admitted to the hospital for further treatment.’
      • ‘You will probably need fresh X-rays and blood tests.’
      • ‘Sometimes, the baby will need tests, such as X-rays or blood tests.’
      • ‘Agenda for Change could see radiographers, who perform X-rays, ultrasound scans and radiotherapy on cancer patients, working a 37.5-hour week.’
      • ‘Often times we suffer from respiratory related diseases like tuberculosis and visit health centres or hospitals for X-rays and ultra sound scanning.’
      • ‘She had a chest X-ray taken today which has gone for reporting.’
      • ‘I'm off for some more blood tests and an X-ray now.’
      • ‘Surgeon Nigel Heaton examined Best before he was taken for blood tests, X-rays and ultrasounds, and then drained away a build-up of fluid which had become infected.’
  • 3A code word representing the letter X, used in radio communication.


[with object]
  • Photograph or examine with X-rays.

    ‘luggage bound for the hold is X-rayed’
    • ‘The physicists had X-rayed the box, looked for magnets, weighed the box to within one micron and analysed the chemical composition of the matches.’
    • ‘My job involves transporting patients from the hospital wards to the radiology department, where they are X-rayed, scanned or receive surgical treatment under radiological observation.’
    • ‘The body is X-rayed from many angles, and the X-rays are then analyzed by a computer.’
    • ‘Mrs Parkin's leg was X-rayed but was not broken.’
    • ‘Casualties are X-rayed to pinpoint the location of coins and some require surgery.’
    • ‘Will the costs of compliance - such as X-raying all foodstuffs and providing lists of every Australian worker who has handled a good destined for the US market - deter Australian companies from exporting to the US in the future?’
    • ‘Doctors who X-rayed his foot at Broomfield Hospital later found the wheel had caused a painful compound fracture.’
    • ‘At the hospital they X-rayed me and the doctor said my collarbone was broken.’
    • ‘They X-rayed me for 50 minutes when I got to hospital, but there were no fractures.’
    • ‘I was X-rayed, and had lots of nurses and doctors coming in and out of the room.’
    • ‘He was taken by ambulance to Bridgwater hospital where he was X-rayed, and then to Taunton for a more thorough examination.’
    • ‘Airport Security Report Indianapolis International Airport: A TSA security screener saw a pair of scissors in a bag that was being X-rayed.’
    • ‘Any part of the body can be X-rayed for information, and they are particularly useful in looking at injuries or changes in bones.’
    • ‘He was X-rayed at another hospital and the condition was diagnosed as ankylosing spondylitis.’
    • ‘For dental X-rays, the dentist or dental hygienist places a small piece of film in your mouth, behind the section of teeth being X-rayed.’
    • ‘If arthritis of the neck is suspected, your neck may be X-rayed.’
    • ‘He said he was then sent to Ward 39 at around 5.30 pm, examined and X-rayed.’
    • ‘Well, it would mean a lot more than X-raying your handbag, removing your shoes, surrendering your tweezers and letting someone pass a metal detector beneath your oxters.’
    • ‘Apparently the mistake my colleague made was to go through her doctor first; if she'd just gone straight to the hospital, said she'd fallen and said she was in considerable pain etc they would have X-rayed her on the day.’
    • ‘Mr Lawrence said: ‘When they X-rayed him they saw the pellet and realised he had been shot.’’


Translation of German X-Strahlen (plural), from X- (because, when discovered in 1895, the nature of the rays was unknown) + Strahl ‘ray’.