銀ぎん河が系けい外がい星せい雲うんぎんがけいがいせいうんMeanings1nounextragalactic nebulaobsolete termastronomy›Obsolete term from early 20th-century astronomy, used before galaxies outside the Milky Way were clearly distinguished from nebulae. Replaced by 銀河 (sense 2) or 系外銀河 in modern usage.See also: 銀河
