1.
planet
A celestial body that orbits a star, is large enough to have cleared its orbital path, and is not a star itself.
惑星 refers to a planet. 惑 means 'bewildered/wandering' (planets appear to wander across the sky) and 星 means 'star.'
THE SOLAR SYSTEM PLANETS:
RELATED TERMS:
NOTE: 冥王星 (Pluto) was reclassified as a 矮小惑星 (dwarf planet) in 2006.