A galaxy is a large, gravitationally bound system of stars, stellar remnants, interstellar gas, dust, and dark matter. The word galaxy is derived from the Greek word galaxias (γαλαξίας), literally "milky", a reference to the Milky Way. Galaxies range in size from dwarfs with just a few hundred million stars to giants with trillions of stars. The Sun is located in the Milky Way galaxy, which is a spiral galaxy with an estimated 200–400 billion stars. The Milky Way is the second largest galaxy in the Local Group, which is a cluster of galaxies that also includes the Andromeda Galaxy and several smaller galaxies. The Local Group is part of the Virgo Supercluster, which is a larger cluster of galaxies that also includes the Coma Cluster and the Perseus Cluster. The Virgo Supercluster is part of the Laniakea Supercluster, which is the largest known supercluster of galaxies.