Singular

A singularity refers to a point where a mathematical model or physical theory breaks down, often involving quantities like density or gravity becoming infinite. In physics, particularly in black hole theory, it describes a region where spacetime curves infinitely, and the laws of physics as we know them cease to apply. In mathematics, a singularity is a point where a function is not well-defined or behaves unpredictably. Essentially, it marks a limit or a boundary where normal rules no longer work, indicating a place where our understanding needs new theories or concepts.