A term used to describe an enormous variety of music. Frequently refers to the traditional music of a region or culture (e.g. Irish music), or people who play/draw from traditional music (e.g. Bob Dylan). Many people like to slap this label on anything with an acoustic guitar (e.g. Jewel), but it's not that easy to define. Like porn, everyone knows it when they see (hear) it. All I know is, it's good and I like it.