- the final stage of stellar evolution in which a star collapses to a final state, as a white dwarf, neutron star, or black hole, when the star's nuclear reactions no longer generate enough pressure to balance the attractive force of gravity.
- the initial stage of stellar evolution in which interstellar gases and dust contract under gravity and condense into one or more stars.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
- The implosion of a star or other celestial body as a result of its own gravity, resulting in a body that is many times smaller and denser than the original body.
- The process by which stars, star clusters, and galaxies form from interstellar gas under the influence of gravity. Clusters of matter are drawn together by gravitational pull, with additional matter continuing to accumulate until the growing nebula develops into even denser gaseous bodies such as stars or groups of stars.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.