Twenty years ago I asked our young English host what a mews was. He replied in some confusion that why it was a Mews. I felt like Alice down the rabbit hole. At home I looked mews up in the Oxford English Dictionary and learned that it was the stables, carriage house, groomsmen's quarters and stable yard attached to a city house, or the houses, flats, gardens or combination thereof built on a former mews. That second definition explained everything including our host's flat and the mews flat we rented last summer.
Language travels strangely. When D.H. Lawrence was writing a lumber room was a place to store unused furniture. Was the furniture lumber? What do the British call boards?