What is Traditional Music?
Traditional Music appears to encompass folk music, at least according to the International Council of Traditional Music whose charter states that:
The aims of the ICTM are to further the study, practice, documentation, preservation and dissemination of traditional music, including folk, popular, classical and urban music, and dance of all countries.
No definition as yet, but the scope seems pretty wide. It gets narrowed by the following on www.traditionalmusic.co.uk:
"TRADITIONAL MUSIC DEFINITION: Songs and tunes which have been performed, by custom, over a long period (usually several generations). They are most often folk songs, country dance or similar types of folk music but they can also be pieces from known early composers and may have been the "pop music " of their time. Traditional music (or public domain) is also used as a copyright status covering music which is out of copyright. In Europe (EEC) music copyright does not expire till 70 years after the death of the composer."
Drawing upon these definitions, I 've come up with my own Traditional Music definition, which is
music passed mostly unchanged between generations of informal players, usually without notation, and played mostly by ear
This definition may change, but it will do for now.