We joke about regional differences in names with mock defensiveness. In Manchester, my area at least, it's a barm and that's that. Even if it isn't technically a barm (not made with barm and is actually sold as a bap).
Oven bottoms are awesome. Those are called barms too. A cob, roll generally means the crusty variety, freshly baked.
A teacake to us is always a barm with currants toasted.
Funny that. I'll need to explore - I didn't realise!