The Little Stranger - halfway through

In between all the chores of the weekend, I have managed to read about half of Sarah Waters' The Little Stranger, wishing I had time to just read it straight through without interruption. I'm wondering about the title - why is it called The Little Stranger? In Victorian times that phrase was used to refer, I think, to an unborn baby. I'm also wondering about the origin of the name of the manor house, Hundreds Hall. How did it come by that name?