Jim, for traditional folksong you already have your 'definition'. I prefer to use the word 'descriptors', but I'm quite happy to use it as A definition.

Any other usage of the word you don't accept so there is no argument.

The other usage of the word 'folksong' as stated above by others is much more loose and defies a definition as do many things that don't have hard and fast boundaries. Even the '54' descriptors are open to interpretation and don't all have hard and fast boundaries as stated by SteveR. You don't accept the wider more loose meaning but you're the only person I know who doesn't.