Isorana

Isorana is a term used in the context of certain types of logic puzzles, particularly those involving a grid and numerical clues. It refers to a situation where a cell in the grid is deducible, or logically solvable, because the available clues and surrounding cells restrict the possible values to only one valid solution. The act of determining the value of that cell is also often called "isorana." The term doesn't have a universally agreed-upon etymology, but it's speculated to have originated within specific puzzle communities online. It is often used informally rather than as a formal mathematical or logical term. The detection of an isorana can drastically simplify the solution process in complex puzzles.