transformation

noun

1. The act of transforming or the state of being transformed.
2. A marked change in appearance or character, especially one for the better.
3. The replacement of the variables in an algebraic expression by their values in terms of another set of variables; a mapping of one space onto another or onto itself; a function that changes the position or direction of the axes of a coordinate system.
4. A rule that systematically converts one syntactic form into another; a sentence derived by such a rule.