The word "traditional" has different meanings in different contexts. The folklorist has a guage by which he/she measures what it traditional by studying the texts of songs and stories told in a sub-culture, generally isolated.
The ethnomusicoligist studies a body of music and compares the style to see if it reflects a culture that dates back many years.
"Traditional" is a term that many have recently applied to a sub-culture-based music collected in rural areas or places where the popular media has not influenced it inordinately but it has survived in spite of the media (radio, recordings, TV etc.)
It could be that "traditional" music is not necessarily folk music if the songs no longer represent a particular sub-culture but are "museum pieces".
The obvious question is whose tradition? Jazz and so-called classical music have a tradition but these may be measured differently by their practitioners.
I think if you put a particular style of music along with traditional, it makes it clear.
"Traditional anglo-American ballads", "Traditional sea chanteys", etc. Then you are talking about a body of work that survives many years not associated with one particular composer or artist but reflects a sub-culture that teaches this way of playing to those within its confines.
I have more to say so I'll post another.