Where the shape comes from
A tongue reaching out past the lips of a mouth 口, its tip forked the way a snake’s or an old stylised tongue was often drawn. Paired with the speech radical it gives 话, speech, words, talk, the tongue that shapes what is said, and it names the act itself in 舔, to lick.
汉字 filed under 舌
No published character on HSK Guide is filed under this radical yet. 汉字库.