singularity

Definition: singularity: In astronomy, a term often used to refer to the center of a black hole, where the curvature of spacetime is maximal. At the singularity, the gravitational tides diverge; no solid object can even theoretically survive hitting the singularity. Mathematically, a singularity is a condition when equations do not give a valid value, and can sometimes be avoided by using a different coordinate system.