龆 is a simplified Chinese hanzi, listed here under the keyword “lose baby teeth and get adult teeth”. It is built from 齿 (teeth) and 召 (imperial decree).
On KumiJi Glyph Explorer, open the parts search and type “teeth” + “imperial decree”. 龆 is among the results, together with every other character containing the same shapes.
Open 龆 in the interactive kanji search
to expand every part down to its smallest pieces, add your own names and mnemonic stories,
or search for other characters by their parts.