Gravitational collapse has 2 different meanings across 1 category:
the implosion of a star resulting from its own gravity; the result is a smaller and denser celestial object
The stage in the evolution of a star in which the pressure of the star is insufficient to maintain it at a stable size, and its material falls inward under its own gravitational attraction, eventually forming a black hole or a neutron star, and sometimes accompanied by a supernova explosion.