Health professionals usually use the term 'traditional medicine' to mean a therapy or health practice that has developed over centuries within a particular culture. It's usually formed around a specific belief system.
This term can be confusing because, in the western part of the world, conventional medicine could be considered traditional medicine. But this term is not usually used in this way. It generally refers to therapies or treatments developed in the eastern part of the world, such as Ayurvedic medicine and traditional Chinese Medicine.