And then there is a style of bed cover based upon the idea of a four poster bed, particularly the large flat panel known as a "tester" (TEE-stir) suspended from the four posts. A half-tester bed is one that only has a short panel above the head of the bed from which falls fabric panels, as seen below. While the look originated centuries ago in Europe, the style today looks elegant and luxurious. The tester can have a valance of some kind, in a shape, even upholstered in fabric.
But when the tester is small or non-existent, and fabric falls from a central point, this is known as a crown. The examples below are rectangular but crowns come in demilune shapes as well for a more regal look!
And here is a literal crown bed...the crown is an actual crown!