Definition of galactic in US English:



  • 1Relating to a galaxy or galaxies, especially the Milky Way galaxy.

    ‘the search for a black hole at the galactic center’
    • ‘The galactic centre of our galaxy is one of Integral's prime targets.’
    • ‘Other sources that contribute to the near-Earth space environment include galactic cosmic ray particles, which originate from outside of the solar system.’
    • ‘The second are galactic cosmic rays, which, although not as lethal as solar flares, represent a continuous background radiation to which the crew would be exposed.’
    • ‘But even shielding does little good against so-called galactic cosmic radiation, which originates in deep space.’
    • ‘The space radiation environment encompasses a broad spectrum of radiation ranging from infra-red to galactic cosmic radiation.’
    • ‘Our Milky Way galaxy is gobbling up its galactic neighbor, Sagittarius, and scientists this week offered documentary proof of this continuing cosmic cannibalism.’
    • ‘In fact, the Sun is at an optimal distance from the galactic centre, called the co-rotation radius.’
    • ‘If accurate, this new view of galactic demography might force astronomers to rethink the fundamentals of galaxy formation.’
    • ‘Radiation could perhaps be a show-stopper because the environment in space - there's galactic cosmic rays.’
    • ‘The galactic centre can only be observed at certain wavelengths, such as X-rays, because large amounts of dust lie in our line of sight and this blocks out optical light.’
    • ‘It was possibly the most important observation but it was just personal observation to sample the glory and the majesty of the galactic plain and the centre of the galaxy.’
    • ‘They are produced in the atmosphere by the interaction of galactic cosmic rays with the atoms of the atmosphere.’
    • ‘The cyclical nature of our weather changes point to the variables in our solar system and even galactic variations.’
    • ‘However, there are larger explosions, notably those that go on in the middle of active galactic nucleii, like quasars.’
    • ‘A coil of a superconducting material could produce a substantial magnetic field, which could, in turn, deflect the energetic galactic cosmic radiation.’
    • ‘They compared the observed shape in space of 160,000 galaxies to models of galactic distribution that incorporated various masses for the neutrino.’
    • ‘Why, given its exceedingly smooth beginnings, is the universe so clumpy, on all scales from galaxies to galactic superclusters?’
    • ‘By contrast, to reach our nearest galactic neighbor, the Andromeda galaxy, you'd need only twenty-five Milky Ways.’
    • ‘A record of the long term variations of the galactic cosmic ray flux can be extracted from Iron meteorites.’
    • ‘In fact, the Universe as observed today seems to have barely a fraction of the mass needed to keep galaxies from flying apart, based on the rotations of the stars in the galaxy about the galactic center.’
    1. 1.1Astronomy Measured relative to the galactic equator.
      ‘the south galactic pole’
      • ‘Out past Fomalhaut, toward the south galactic pole, the stars fade.’
      • ‘This map is plotted in galactic coordinates - the plane of the Milky Way galaxy passes across the middle of this chart with the zero point of galactic latitude and longitude pointing directly at the galactic centre.’


Mid 19th century: from Greek galaktias (variant of galaxias ‘galaxy’) + -ic.