cosmic ray

noun

Definition of cosmic ray

  1. :  a stream of atomic nuclei of extremely penetrating character that enter the earth's atmosphere from outer space at speeds approaching that of light

1925

First Known Use of cosmic ray

1925


COSMIC RAY Defined for English Language Learners

cosmic ray

noun

Definition of cosmic ray for English Language Learners

  • : a stream of energy that enters the Earth's atmosphere from outer space


COSMIC RAY Defined for Kids

cosmic ray

noun

Definition of cosmic ray for Students

  1. :  a stream of very penetrating particles that enter the earth's atmosphere from outer space at high speed


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