Where the shape comes from
A pair of feathers side by side, the fine barbs branching off the central shaft on each. A bird’s wing shown moving above 日 or 白 gives 习, to practice, to learn, from a fledgling beating its wings again and again over open ground before it can fly; and it names the wing directly in 翅, a wing, a fin.
汉字 filed under 羽
No published character on HSK Guide is filed under this radical yet. 汉字库.