歎 is a Chinese hanzi, listed here under the keyword “sigh”. It is built from 廿 (twenty), 口 (mouth), 夫 (man) and 欠 (owe). It appears as a component in 1 other character in this index.
On KumiJi Glyph Explorer, open the parts search and type “twenty” + “mouth” + “man”. 歎 is among the results, together with every other character containing the same shapes.
Open 歎 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.