This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
砡 combines 石 (stone) and 玉 (jewel). The exact historical development and original meaning are uncertain.
The left side is stone 石 and the right side is jewel 玉. Imagine a rough stone that contains a hidden jewel, but the kanji's meaning remains unclear.
For ギク, imagine a geeky stone collector polishing a jewel: geek -> ギク, and the stone 石 and jewel 玉 are together.