- The Milky Way, that luminous tract, or belt, which is seen at night stretching across the heavens, and which is composed of innumerable stars, so distant and blended as to be distinguishable only with the telescope.
- A very large collection of stars comparable in size to the Milky Way system, held together by gravitational force and separated from other such star systems by large distances of mostly empty space. Galaxies vary widely in shape and size, the most common nearby galaxies being over 70,000 light years in diameter and separated from each other by even larger distances. The number of stars in one galaxy varies, and may extend into the hundreds of billions.
- A splendid or impressive assemblage of persons or things; as, a galaxy of movie stars.
Etymology: F. galaxie, L. galaxias, fr. Gr. � (sc. � circle), fr. �, �, milk; akin to L. lac. Cf. Lacteal