Almost but not quite.

To rathole is to take money off a table - simple as that. It is commonly associated with shortstacking, or to be more specific if you are only willing to play with a given stack size. You can leave a table and rejoin the same table with a stack of your preferred size which is the epitome of ratholing - but just leaving a table when your stack is too big for what you feel comfortable with is also ratholing.

It is a derogatory term, usually used by people who want to take your moneyz and who wants you to think that leaving before you've lost your money to them is somehow a bad thing. There's really nothing wrong with choosing to limit your exposure in any game that you have decided to play.