Room size

Sorry if this has been discussed. How big is a large room? Medium size room? Size is always mentioned, but dimensions rarely given. My room is 14x21 with ceilings that go from 7 ft to a peak of 13 ft and back down to 7 ft. Is this considered a large or medium size room? Im considering going to a monitor speaker (Totem perhaps) and wonder if they will be fine or too small for a room this size. Thanks to all who reply.