melon, wrap
陏 centers on a melon-like shape that can wrap or enclose something. The meanings 'melon' and 'wrap' are loosely connected through the idea of a rounded, enveloping form.
The historical origin of 陏 is uncertain. It combines ⻖ (mound, hill) with 有 (have, exist), but how these components produce the meanings 'melon' or 'wrap' is unclear.
Picture a mound ⻖ with a rounded melon 有 growing on it. The melon's vine wraps around the mound, linking 'melon' and 'wrap'.
For ダ, imagine a melon wrapped in a dark cloth: dark -> ダ, and the wrapped melon sits on the mound.