alms bowl, small bell
釪 centers on a small metal vessel used in religious contexts: an alms bowl for collecting offerings, or a small bell that might be rung during rituals.
釪 combines 金 (metal) with 于, which likely contributes the sound. The character refers to metal objects used in Buddhist practice, but the exact historical development is uncertain.
The left side is 金 (metal), and the right side 于 looks like a small bowl with a handle. Picture a metal alms bowl or a small metal bell used by monks.
For ウ, imagine a monk holding the metal bowl and softly saying 'oo' as they receive alms: the 'oo' sound cues ウ.