Flat - the wing is shaped like a circular disc with a hole in it.
As an example suppose that is a circular disc.
Again, consider the example in which is a circular disc.
Inside they saw a circular disc about 10 feet in diameter, made of a transparent plastic material.
He was holding something in each of his hands, a circular disc, padded, trailing electric wires.
A roughly circular disc had been cut to the depth of the wire.
This device consisted of two circular discs one with a larger diameter.
Its rear end has become a completely flat, circular disc of armour.
This eye, "a small, circular disc, brown with a black center, was dreadful to behold."
A combination of red, green and blue in the circular disc will yield the same result.