We found 19 dictionaries that define the word cosmic ray:

General (14 matching dictionaries)

1. cosmic ray: Merriam-Webster
2. cosmic ray: Oxford Learner's Dictionaries
3. cosmic ray: American Heritage Dictionary of the English Language
4. cosmic ray: Vocabulary.com
5. Cosmic-ray, cosmic-ray: Wordnik
6. cosmic ray: Wiktionary
7. cosmic ray: Infoplease Dictionary
8. cosmic ray: Dictionary.com
9. Cosmic Ray (film), Cosmic Ray, Cosmic-ray, Cosmic ray: Wikipedia, the Free Encyclopedia
10. cosmic ray: Rhymezone
11. cosmic ray: FreeDictionary.org
12. cosmic ray: Mnemonic Dictionary
13. cosmic ray: TheFreeDictionary.com
14. cosmic ray: Longman Dictionary of Contemporary English

Computing (1 matching dictionary)

15. Cosmic-ray, cosmic ray: Encyclopedia

Medicine (1 matching dictionary)

16. cosmic ray: Medical dictionary

Science (1 matching dictionary)

17. cosmic ray: Nine Planets Glossary

Tech (2 matching dictionaries)

18. National Weather Service Glossary (No longer online)
19. SOLAR-TERRESTRIAL TERMS (No longer online)

(Note: See cosmic_rays as well.)

Definitions from Wiktionary (cosmic ray) ▸ noun:  (astronomy) An energetic particle originating outside our solar system. ▸ noun:  (astronomy) Cosmic radiation: a stream of cosmic rays. Similar: cosmic radiation, astroparticle, solar energetic particle, cosmic background radiation, cosmoparticle, cosmic dust, derma ray, delta ray, cosmic neutrino background, solar radiation, more... Opposite: terrestrial ray, solar radiation Types: proton, electron, muon, neutrino, gamma ray, more... Phrases: cosmic ray shower, Ultra-high-energy cosmic ray, Cosmic ray spallation, Cosmic ray visual phenomena, Cosmic Quantum Ray, more... ▸ Words similar to cosmic ray ▸ Usage examples for cosmic ray ▸ Idioms related to cosmic ray ▸ Wikipedia articles (New!) ▸ Words that often appear near cosmic ray ▸ Rhymes of cosmic ray ▸ Invented words related to cosmic ray