Definition of cosmic ray in English:

cosmic ray

Line breaks: cos¦mic ray

noun

A highly energetic atomic nucleus or other particle travelling through space at a speed approaching that of light.
More example sentences
  • This radioactive isotope is created when energetic particles in cosmic rays enter the Earth's atmosphere and split atomic nuclei of nitrogen and oxygen.
  • Other sources that contribute to the near-Earth space environment include galactic cosmic ray particles, which originate from outside of the solar system.
  • The Moon's regolith was created by the ceaseless bombardment of micrometeorites, cosmic rays and particles of solar wind breaking down rocks for billions of years.

Definition of cosmic ray in:

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Word of the day hubris
Pronunciation: ˈ(h)yo͞obris
noun
excessive pride or self-confidence