dumpling, supply
餫 centers on providing food or provisions: a dumpling as a specific food item, and the broader act of supplying or sending provisions.
餫 combines 飠 (food) with 軍, which likely contributes the sound and may relate to transporting or distributing provisions. The exact historical development is uncertain.
The food radical 飠 beside 軍 (army) suggests army provisions: imagine a dumpling being supplied to soldiers.
For ウン, picture a dumpling being delivered by a courier service named 'Un': Un -> ウン, and the dumpling is the supply.