It's often used to convey the idea of correctness, straightness, or orderliness.
Here are some examples of words with the prefix "rect":
* Rectangle: A four-sided figure with four right angles.
* Rectify: To correct something that is wrong.
* Rectangular: Having the shape of a rectangle.
* Rectitude: Moral uprightness or righteousness.
* Direct: Straightforward or to the point.
* Erect: To build or construct something, especially a structure.