(n)square, foursquare(geometry) a plane rectangle with four equal sides and four right angles; a four-sided regular polygon“you can compute the area of a square if you know the length of its sides”
(n)square, second powerthe product of two equal terms“nine is the second power of three”, “gravity is inversely proportional to the square of the distance”
(n)squarea hand tool consisting of two straight arms at right angles; used to construct or test right angles“the carpenter who built this room must have lost his square”