The Latin word I would use for to translate "philosophy" is philosophia. But this is a transliteration of a Greek word. Is there an originally Latin word for "philosophy"? The closest word I could find is sapientia, but it doesn't seem to have the same nuance as philosophia. Does philosophia have a closer Latin equivalent than sapientia? I would assume the Romans had a word for their philosophical literature.
Romans acknowledged that this was a Greek term:
Ita fit ut mater omnium bonarum rerum sapientia, a quoius amore Graeco
uerbo philosophia nomen inuenit, qua nihil a dis immortalibus uberius, nihil florentius, nihil praestabilius hominum uitae datum est. (Cicero, De Legibus 1.58)
Thus it is that the mother of all good things is wisdom, from whose love philosophy found its name in a Greek word: nothing has been given to the life of men by the immortal gods that is more fertile, fruitful, and excellent.
Further evidence that a native term for this was never in widespread use comes from De Officiis. Given Cicero's proclivity for inventing Latin neologisms for Greek philosophical terms, it is significant that he views the studium sapientiae as a one-off translation while continuing to use philosophia afterwards:
nec quicquam aliud est philosophia, si interpretari velis, praeter studium sapientiae. (Cicero, De Officiis 2.5)
Philosophy, if you wish to translate the word, is nothing other than the love of wisdom.