主しゅ星せいしゅせいMeanings1nounprimary starastronomyAstronomical term for the main star in a binary or multiple star system, or the central star around which planets orbit.この連れん星せい系けいでは、主しゅ星せいの周まわりを伴ばん星せいが回まわっている。In this binary system, the companion star orbits around the primary star.