We found 18 dictionaries that define the word periastron:

General (13 matching dictionaries)

1. periastron: Merriam-Webster
2. periastron: Oxford Learner's Dictionaries
3. periastron: Collins English Dictionary
4. periastron: Wordnik
5. periastron: Wiktionary
6. periastron: Infoplease Dictionary
7. periastron: Dictionary.com
8. Periastron: Wikipedia, the Free Encyclopedia
9. Periastron: Online Plain Text English Dictionary
10. periastron: Webster's Revised Unabridged, 1913 Edition
11. Periastron: AllWords.com Multi-Lingual Dictionary
12. periastron: FreeDictionary.org
13. periastron: TheFreeDictionary.com

Computing (1 matching dictionary)

14. periastron: Encyclopedia

Medicine (1 matching dictionary)

15. online medical dictionary (No longer online)

Science (2 matching dictionaries)

16. Imagine the Universe! Dictionary (No longer online)
17. Periastron: Extragalactic Astronomy

Tech (1 matching dictionary)

18. High-Energy Astrophysics (No longer online)

Definitions from Wiktionary (periastron) ▸ noun:  (astronomy) That point of the orbit of a celestial body which is closest to the star around which the body is orbiting. Similar: apastron, apoastron, pericenter, periapsis, periareion, peribothron, apsis, apoapsis, perigee, apocenter, more... Opposite: apastron, apsis, furthest point, farthest point Types: periastron distance, periastron passage, periastron shift, periastron advance, more... ▸ Words similar to periastron ▸ Usage examples for periastron ▸ Idioms related to periastron ▸ Wikipedia articles (New!) ▸ Popular adjectives describing periastron ▸ Words that often appear near periastron ▸ Rhymes of periastron ▸ Invented words related to periastron