• 小説しょうせつ — novel
• 説明せつめい — explanation
• 伝説でんせつ — legend
• 説得せっとく — persuasion
• 解説かいせつ — commentary
• 仮説かせつ — hypothesis
• 講説こうせつ — public lecture

The left part of this character is 言ことば — the radical for speech. The right part represents movement or guidance. Together, the kanji originally expressed the idea of “speaking clearly to guide understanding.”

This is why it appears in words related to stories, theories, and explanation — like 小説しょうせつ (novel) and 説得せっとく (persuasion).

先生せんせいが 丁寧ていねいに 説といてくれました。
The teacher explained it carefully.

彼かれを 説得せっとくするのは 難むずかしい。
It’s difficult to persuade him.

The reading “せつ” (setsu) appears in both technical and everyday words, while the kun-yomi “とく” is used when the meaning is closer to “explain.” You’ll often see it in formal Japanese and academic speech.