(games, puzzles) A type of pencil puzzle played on a square grid, requiring each of the columns, each of the rows, and each of the subregions (called "boxes" or "regions") to contain the lowest whole numbers up to the dimension of the puzzle, usually 1 to 9, once each. The subregions are rectangular or square except in variants.

plural of sudoku

A sudoku variant where the grid also contains cages which must sum to the total where indicated, without repeating any digit within the cage.

plural of sandwich sudoku

A sudoku variant where numbers outside the grid indicate the sum of the digits sandwiched between the digits 1 and 9 in the corresponding row or column.

plural of killer sudoku

(Internet slang, humorous) To commit seppuku.

(rare) A person who solves sudoku puzzles.

plural of sudokuist