A sigil is a type of symbol used in magic. The term usually refers to a pictorial signature of a deity or spirit. In modern usage, especially in the context of chaos magic, a sigil refers to a symbolic representation of the practitioner's desired outcome.

In recreational mathematics, a square array of numbers, usually positive integers, is called a magic square if the sums of the numbers in each row, each column, and both main diagonals are the same. The 'order' of the magic square is the number of integers along one side (n), and the constant sum is called the 'magic constant'. If the array includes just the positive integers , the magic square is said to be 'normal'. Some authors take magic square to mean normal magic square.