bowl, basin, cup
盌 centers on a container for holding liquids or solids: a bowl, basin, or cup. The meanings are straightforward physical objects with no strong abstract extensions.
盌 combines 皿 (dish, vessel) with 夗, which likely contributes a phonetic element. The character is a traditional form for a bowl or basin.
The bottom 皿 is a dish or plate, and the top 夗 looks like a curved container. Together they form a deep bowl or cup.
For ワン, picture a one-of-a-kind bowl: one -> ワン, and the bowl is the only one you need.
—