Cris, I've Googled every possible spelling and found nothing, and I can't say I've ever heard of it.
Devon is notorious for mis-hearings. I guess anywhere with a strong accent coupled with dialect is liable to be.
I knew of a chap who, after being told how to lay patio slabs, went around every builders merchant he could find to try and get some "beddemin" sand. No one had heard of it until someone figured out he'd been told to ....... "bed them in" sand ;o)