Today's BWOTD is an old-fashioned term:
"I fancy some elevensies, do you?"
'Elevensies' = mid-morning snack
This obviously derives from the fact that a mid-morning snack would be eaten around 11am. You used to hear this alot on TV and in person, but nowadays it is not as common. It's still a cute Brit' phrase though and most Brit's would know what you mean't by this.