I'm not forgetting that Enduro has different meanings in the UK, that's part of the point. Stamping your foot and saying that one meaning is more "right" than the other meaning just makes you look childish, especially the CAPS SHOUTING. I also don't know anyone in the UK or at any of the 12 and 24h enduros I did that would call it Marathon XC, whatever the UCI might have to say about that. Saying that you just did a 24h Marathon XC event would have your mates rolling around laughing and calling you a knob jockey.
It's also worth pointing out that there is really very little terrain in England (Scotland and Wales is a bit different) where you can hold Euro-style Enduro events - there aren't huge swathes of connected off-road trails and no mountains to speak of. There's a reason why the UK's World Cup DH race is held in Scotland you know..