nonlinear

adjective

1. 1

   (of a set of points) Not lying on a straight line.

2. 2

   (of a molecule) Whose atoms do not lie in a straight line.

3. 3

   (of a function) Having a product of independent variables, or a variable with an exponent not equal to one.

4. 4

   (of a system) Whose output is not directly proportional to its input.

5. 5

   Erratic and unpredictable; tending to jump back and forth.

   “a film with a nonlinear plot”