The crossword solution for the term 'LENGTH X WIDTH, FOR A RECTANGLE' is AREA. The AREA of a rectangle is calculated by multiplying the length and width of the rectangle together. This formula is used to determine the size of a two-dimensional shape, such as a rectangle, square, or parallelogram. Knowing the AREA of a rectangle can be useful in many situations, such as when calculating the amount of material needed to cover a certain AREA.