periastron

P3E1R1I1A1S1T1R1O1N1
/pɛɹɪˈæstɹən/

noun

The point of an orbit in which a celestial body is at its closest to the star it is orbiting.

Opposite
apastron
OriginAncient Greek περί →
Scrabble 12
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Meanings

nounperiastron (plural periastrons or periastra)

plural periastrons · plural periastra

  1. astronomyThe point of an orbit in which a celestial body is at its closest to the star it is orbiting.

Synonyms & antonyms

Opposite
apastron

Origin

  1. Ancient Greekπερί“around”
  2. Englishperiastron

From Ancient Greek περί (perí, “around”) + ἄστρον (ástron, “star”).

More words from Ancient Greek

Full word history & related roots →

Translations

Bulgarian периастрий
  • периастрий (periastrij)point of least separation between a celestial object and the star which it orbits
Finnish periastron
  • periastronpoint of least separation between a celestial object and the star which it orbits
Polish peryastron
  • peryastronpoint of least separation between a celestial object and the star which it orbits
Cite this entry
APA

periastron. (n.d.). In WatkinsX Dictionary. Retrieved November 3, 2026, from https://dictionary.watkinsx.com/word/periastron

MLA

“periastron.” WatkinsX Dictionary, https://dictionary.watkinsx.com/word/periastron. Accessed November 3, 2026.

Chicago

WatkinsX Dictionary, s.v. “periastron,” accessed November 3, 2026, https://dictionary.watkinsx.com/word/periastron.

Source: periastron on Wiktionary, CC BY-SA 4.0.