While you are right that 毒 (doku) means 'poison', the Japanese word for 'sudoku' is 数独[1]. 数 (su) = number, numeral, digit 独 (doku) = alone, solitary, single

While you are right that 毒 (doku) means 'poison', the Japanese word for 'sudoku' is 数独[1]. 数 (su) = number, numeral, digit 独 (doku) = alone, solitary, single This conveys the idea that the digits may only appear once per {row, column, box}. [1]: https://jisho.org/search/sudoku https://jisho.org/search/sudoku