This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鉧 combines 金 (metal) with 母, but the historical origin and meaning are uncertain. It may be a kokuji or a specialized character for a metal-related term.
With no clear meaning, picture a rare metal object shaped like a mother figure: 金 (metal) + 母 (mother). This unusual image can help you remember the character's shape.
For ボウ, imagine a metal bowl (ボウ) made from this rare metal: bowl -> ボウ, and the bowl is crafted from the mysterious 鉧 material.