noun col·lap·sar \kə-ˈlap-ˌsär\

Definition of collapsar



  1. :  a massive star that undergoes gravitational collapse especially after colliding with another star Collapsars are massive stars, which in the course of merging with a compact companion undergo core collapse leading to a BH [black hole] … leaving a supernova-like remnant. — P. Mészáros, Science, 5 Jan. 2001 Today most astronomers think gamma-ray bursts result when a massive and rapidly rotating star collapses in on itself to form a black hole. The collapsing star, or collapsar, is a kind of supernova, but the extraordinary heft and spin of the star bring it to a faster and more calamitous end. — Karen Wright, Discover, August 2002; broadly :  black hole 2 This classification of stars results in three main types: regular stars (covering white dwarfs to super-giants) …, neutron stars and pulsars, … and collapsars (i.e. black holes) … . — Pierre A. Millette, Progress in Physics, January 2014

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Origin and Etymology of collapsar

1collapse + -ar (as in quasar)

First Known Use: 1971

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a dividing ridge between drainage areas

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