The maximum possible mass for a stable white dwarf star. A star exceeding this mass will eventually collapse into a much denser state such as a neutron star or black hole. The limit is named after Indian astrophysicist Subrahmanyan Chandrasekhar who first calculated it accurately in 1930. It's equal to 1.39 solar masses.
The Sun does not exceed the Chandrasekhar limit and therefore our star will eventually evolve into and end its life as a white dwarf.