Square Root
in mathematics, a quantity which, being taken twice as a factor, will produce the given quantity.
Thus, the square root of 25 is 5, because 5×5=25; so also 2-3 is the square root of, since; x² is the square root of x, x², since x² Xx²=x²; a+x is the square root of a²+2ax+x², and so on. When the square root of a number can be expressed in exact parts of 1, that number is a perfect square, and the indicated square root is said to be commensurable. All other indicated square roots are incommensurable.