This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
鉵 combines 金 (metal) and 虫 (insect). The exact historical development and original meaning are uncertain.
The kanji visually combines metal 金 and insect 虫, but its meaning is unclear. Picture a metal insect as a placeholder image.
For トウ, imagine a metal insect tapping with a toe: toe -> トウ, though the meaning remains uncertain.