The 'living in the dim and distant past' jibe was aimed at those who won't accept that songs written over the last 60 years and those written in the last year can't be folk songs by any definition. They are being written, sung and listened to by people on the 'folk scene'. There you go, Jim, there's a definition for you.

To go back to the OP I suggest you go to a recent edition of a comprehensive dictionary that is annually updated. Not much use going to the one on the shelf that's sat there for 30 years for up-to-date definitions.