That is the name scientists have given the gigantic super-cluster of galaxies that contains our Milky Way. The word means "immeasurable heaven" in Hawaiian - an appropriate description for a structure 500 million light years across that contains 100,000 galaxies and a hundred quadrillion suns.
Laniakea itself forms just one corner of the observable universe. Scientists have long-known that galaxies are not distributed randomly but congregate together in clusters.
Dr Brent Tully, from the University of Hawaii in Honolulu, led the team of scientists that mapped the super-cluster's boundaries from measurements of the velocities of local galaxies.
They wrote in the journal Nature: "We define a supercluster to be the volume within such a surface, and so we are defining the extent of our home super-cluster, which we call Laniakea."