The terms have different emphases, but you will find no “formal definition” for them. “Traditional” suggests a preference for older liturgical and devotional styles; a similar word, “Traditionalist,” has a somewhat different emphasis and is used to label those intent on restoring the old Latin Mass. One can be “traditional” without being “Traditionalist” in that sense. “Orthodox” means “having the right opinion,” and everyone should strive to be that; it’s a handy word when used in contradistinction to “heterodox, ” which means “having a different opinion (from the official teaching). ” “Conservative” is a political term injected into religion, and I recommend against using it if some other word will convey your point.
Final advice: Don’t worry about trying to pigeonhole yourself. Learn to be satisfied with just calling yourself “Catholic. “