Galaxy (noun)

1. A system of millions or billions of stars, together with gas, dust, and dark matter, held together by gravitational attraction.
2. A collection of similar objects or people.

Origin:

Late 16th century: from greek galaxias, from gala 'milk' + -axia 'having the nature of' (because the milky way was thought to resemble a spill of milk in the night sky).

Examples:

1. The Milky Way is a barred spiral galaxy.
2. The film industry is a galaxy of stars and talented people.
3. Astronomers have discovered a new galaxy in the observable universe.
4. The galaxy of galaxies is known as the universe.
5. The galaxy is thought to be around 13.8 billion years old.