cosmic ray

noun

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

Examples of cosmic ray in a Sentence

Recent Examples on the Web

High-energy accelerators help scientists test these space technologies and prepare them to stand up to radiation from cosmic rays. — Andrea Richard, The Conversation, 2 Oct. 2026

Natural cosmic ray muography yields only about 1 muon per square centimeter per second. — Mrigakshi Dixit, Interesting Engineering, 2 Oct. 2026

This celestial shield keeps harmful solar wind, cosmic rays and radiation at bay, preventing the atmosphere from being stripped away. — Jacopo Prisco, CNN Money, 29 Sep. 2026

For nearly 50 years, the instrument has provided constant measurements on the ion, electron and cosmic ray environment in deep space. — Tariq Malik, Space.com, 5 Sep. 2026

Word History

First Known Use

1925, in the meaning defined above

Rhymes for cosmic ray

• aaa
• alleyway
• alumnae
• anime
• anyway
• arete
• attache
• axillae
• baa
• beaujolais
• bouvier
• breakaway

Kids Definition

cosmic ray

noun

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