Well as I remember, traditional comes from the Latin word traditio - meaning I hand over.

Unfortunately if your parents handed over to you a love of rock n roll, George Formby and frank Sinatra - it doesn't really cut much ice amongst traditional music fans. Your parents didn't traditio you the right stuff.

a rough translation would seem to be nowadays "whatever it is that makes you feel superior to pop music fans" - none of whom dance jigs!