Definition of apastron in English:

apastron

noun

Astronomy
  • The point in the path of a celestial object orbiting a star at which it is farthest from the star.

Origin

Mid 19th century; earliest use found in William H. Smyth (1788–1865), naval officer and surveyor. From apo- + ancient Greek ἄστρον star, after aphelion.

Pronunciation

apastron

/aˈpastr(ə)n/