corner
窔 centers on a deep, secluded corner or recess, often within a room or cave-like space. The given meaning 'corner' reflects this idea of a hidden, innermost nook.
窔 combines 穴 (hole, cave) with 交 (mix, intersect), possibly suggesting a deep intersecting corner within a cave or room. The exact historical development is uncertain.
Imagine a cave (穴) with intersecting passages (交) that lead to a deep, dark corner. That hidden nook is 窔.
For ヨウ, picture a yo-yo lost in the deepest corner of the cave: yo -> ヨウ, and you have to search the corner to find it.