Definition of ultraviolet in English:



  • 1(of electromagnetic radiation) having a wavelength shorter than that of the violet end of the visible spectrum but longer than that of X-rays.

    • ‘They may also be protective in skin conditions attributed to excessive ultraviolet light exposure.’
    • ‘But what is so special about water that makes its absorptions extend all the way from the far infrared to the near ultraviolet?’
    • ‘Most medical lasers emit light which are either ultraviolet, infrared or in the visible spectrum of light.’
    • ‘The ultraviolet flash from the supernova explosion, which we first saw 18 years ago, ionized the ring and causes it to glow.’
    • ‘Excessive ultraviolet ray exposure can cause premature aging of the skin, cataracts, skin cancers and immune system suppression.’
    • ‘The ultraviolet reflectance of web decorations may play an important role in sensory exploitation.’
    • ‘Damage to the eyes can be prevented by wearing sunglasses with 100-percent ultraviolet blocking.’
    • ‘Depletion of the Earth's ozone layer is considered responsible for an increase in the solar ultraviolet irradiance reaching the surface.’
    • ‘However, color display as well as camouflage is likely to involve visual signals, ambient light, and/or photoreceptors notably active in the near ultraviolet to which humans are not sensitive.’
    • ‘It is true that ultraviolet light causes mutations in all living organisms.’
    • ‘Energy reaches earth from the sun in rays of invisible ultraviolet light.’
    • ‘Binders must have specific properties such as good adhesion, abrasion resistance, the ability to cure at room temperature, water resistance and ultraviolet light resistance.’
    • ‘This is an ‘enhanced true color’ view spanning ultraviolet to infrared wavelengths.’
    • ‘Investigators assume that ultraviolet light is the most important factor for the initiation of malignant melanoma.’
    • ‘The bulbs are covered with a plastic screen that helps block out potentially harmful ultraviolet rays that can cause cataracts and skin problems.’
    • ‘The functional significance of vertebrate ultraviolet vision has been the focus of an increasing number of research studies over the last decade.’
    • ‘Disinfecting by ozonization or ultraviolet light methods are replacing chlorine in some water treatment plants, but are not yet readily available for home use.’
    • ‘Diode lasers are now available in discrete colors from the infrared to blue and into the near ultraviolet.’
    • ‘Each cluster size emits at a different wavelength, producing ultraviolet, blue, green, red and infrared fluorescence, with the smaller structures being more efficient emitters.’
    • ‘The liquid materials are photosensitive polymers that solidify when exposed to either laser or ultraviolet light.’
    • ‘Optional Low-E glass coatings help reduce heat and ultraviolet rays that can fade carpet, walls and furniture.’
    • ‘A hat could tell you how much ultraviolet light you're being exposed to.’
    • ‘The reason we need sunglasses in the first place is to protect our eyes from the sun's harmful ultraviolet rays.’
    • ‘Sand on beaches, concrete pavements and snow also reflect up to 40% of the harmful ultraviolet rays.’
    • ‘Finally, the Ultraviolet Imaging Spectrograph, or UVIS, studies wavelengths shorter than humans can see, out to the far ultraviolet.’
    1. 1.1 (of equipment or techniques) using or concerned with ultraviolet radiation.
      ‘an ultraviolet telescope’
      • ‘The bands containing labeled oligonucleotide were identified by visual inspection and ultraviolet shadowing.’
      • ‘Deep ultraviolet photolithographically defined ultra-thin films for selective cell adhesion and outgrowth and method of manufacturing the same and devices containing the same’
      • ‘Community Beat Officer Tracy Finn said police had devised an ultraviolet marking scheme to tackle the problem, but they need more people to come forward and pick up the pens to make it a success.’
      • ‘Taylor advised students ‘to help the police and yourself and keep all laptops and computers out of sight, and have valuables marked with ultraviolet pens to help us trace stolen property.’’
      • ‘The escalating cost of these tools for conventional optical and extreme ultraviolet lithography is driven in part by the need for complex optical sources and optics.’
      • ‘Last summer Japanese inventors unveiled a tiny ultraviolet light sensor for cell phone users concerned about sunburn.’
      • ‘The PCR products were analyzed by electrophoresis on agarose gels containing ethidium bromide and were photographed under ultraviolet transillumination.’
      • ‘After that, it flows through a high intensity ultraviolet light unit, which kills any remaining organisms.’
      • ‘The ultraviolet beam of an argon laser operating at 364 and 351 nm is used to photolyze caged-nucleotide.’
      • ‘The processor industry-backed company developing extreme ultraviolet lithography chip-making equipment has demonstrated its first prototype.’
      • ‘The 59-year-old women were both photographed with special ultraviolet cameras that captured every sun-induced blemish on their faces and another camera that recorded wrinkles.’
      • ‘We allowed systemic antihistamines, but no other systemic treatment or ultraviolet light treatment was permitted.’
      • ‘An ultraviolet filter kills bacteria in a central tank with blasts of artificial light, but the risk remains that water will become contaminated in the pipes carrying it to homes.’
      • ‘The ultraviolet photo shows the true extent of damage to her skin.’
      • ‘The flower on the right was photographed in normal light, the one on the left in ultraviolet (he goes into the technique in some detail).’
      • ‘With final ultraviolet light treatment, the effluent has been treated for everything but viruses.’
      • ‘In addition to its suite of cameras, Skylab was stocked with tons of scientific equipment, including coronagraphs, spectrometers, and ultraviolet and X-ray telescopes.’
      • ‘The samples were tested for fluorescence in a darkened room with 4-watt long- and shortwave ultraviolet lamps.’


mass nounPhysics
  • The ultraviolet part of the spectrum; ultraviolet radiation.

    • ‘The ultraviolet radiation in natural sunlight was later identified as a mutagen.’
    • ‘Broad-spectrum ultraviolet radiation from the sun or artificial light sources was added as a known carcinogen.’
    • ‘As the temperature rises, the maximum intensity of the radiated light moves into the red, then extends through the spectrum to the ultraviolet.’
    • ‘Unless the ship was scanned, it was invisible, since its engines were tuned to emit only in the ultraviolet.’
    • ‘To concentrate on the ultraviolet part of the spectrum, we calculated the proportion of the ultraviolet in each plumage spectrum measured.’
    • ‘When nosing around for protection, you want lenses that block ultraviolet (UVB and UVA) light radiation.’
    • ‘The white crystals fluoresce blue-white in longwave ultraviolet radiation while the yellowish crystals fluoresce lemon-yellow.’
    • ‘Solar ultraviolet radiation is thought to be the culprit.’
    • ‘The amount of solar ultraviolet radiation at the earth's surface depends on the incoming solar energy and on the transmission properties of the atmosphere.’
    • ‘Solar radiation is made up of three forms of energy: about 5 percent ultraviolet, 45 percent visible light, and 50 percent infrared.’
    • ‘When many sunspots are visible, the Sun is somewhat brighter than in ‘quiet’ times and radiates considerably more in the ultraviolet.’
    • ‘The ozone decline is expected to produce an increase in the ultraviolet radiation at the ground.’
    • ‘Injury thresholds resulting from exposure of less than 10 seconds to the skin from far infrared and far ultraviolet radiation are very superficial and may involve changes to the outer dead layer of the skin.’
    • ‘The combination of trauma from the oxygen mask and ultraviolet from the lights in the operating theatre resulted in formation of a subepidermal blister and consequently an erosion.’
    • ‘Although some ultraviolet radiation passes through his level to be absorbed by ozone in the stratosphere, the most harmful radiation is absorbed at altitudes above 80 km.’
    • ‘Siegel and Toole found that ultraviolet radiation explained almost 90 percent of the variability in the biological production of DMS.’
    • ‘Once CFCs are released into the atmosphere, only strong ultraviolet radiation can break them down.’
    • ‘This is one of the few big instruments that will be good in the ultraviolet.’
    • ‘A more accurate map shows a wash of differing hues of indigo and violet, with some smatterings of infrared and ultraviolet at the extremes.’
    • ‘Long ultraviolet would get down to the earth if there were no ozone.’