sidereal

/saɪˈdɪriəl/
adjective
  1. Relating to the stars or the constellations.
    • Sidereal navigation was used by ancient sailors to find their way across the ocean.
    • The sidereal year is based on the position of the stars, not the seasons.
    • Astronomers study sidereal movements to understand the galaxy's structure.
Antonyms
What does "sidereal" mean? | whatsthatwordmean | whatsthatwordmean