n. In geometry, a regular body with six square faces; a rectangular parallelopiped, having all its edges equal.n. In arithmetic and algebra, the product obtained by multiplying the square of a quantity by the quantity itself; the third power of a quantity: as, 4 × 4 × 4 = 64, the cube of 4; a is the cube of a, or x of x.To raise to the cube or third power. See cube, n., 2.To measure the cubic capacity of a hollow object, like that of a skull.