metal flow, (kokuji)
𨫤 is a rare kokuji (Japanese-made kanji) that centers on the flow or movement of metal, likely in a molten or liquid state.
𨫤 is a kokuji, likely created in Japan by combining 金 (metal) with a phonetic or semantic component containing マ, 用, and 辶 to express the idea of metal flowing. The exact historical development is uncertain.
The left side is 金 (metal), and the right side combines マ, 用, and 辶 (movement). Picture molten metal moving and flowing like a river, guided by the shape of the right components.
For ひ, imagine the hissing sound of hot metal flowing: 'hii' — the sound of steam rising as the metal moves. Hii -> ひ.