Considering that politics is about the exchange of ideas between people so a society can be governed (by whatever system applies) and laws can be enacted to make that government functional, I would consider political basically the political process itself, laws, philosophy, maybe history (which informs the other ones and usually has some inherent biases), maybe literature (the same) and a few other disciplines. Mostly things that are by nature subjective and can't be measured in an objective way (like math, or engineering in general can).

That doesn't mean that the latter can't be "contamined" by politics, especially the disciplines which are a mixed bag of objectivity and subjectivity, like architecture or the economical sciences. But that's why the key word here is "inherently": those disciplines are not inherently political, they've been co-opted by interest groups precisely because of that subjectivity.