noun
Literary or formal noun for a feeling of personal delight or contentment. Often used in compound words like 悦に入る (to be self-satisfied) or 法悦 (religious ecstasy).
彼は自分の成功に悦に入っている。
He is basking in self-satisfaction over his success.
その知らせを聞いて、彼女の顔に悦の色が浮かんだ。
Upon hearing the news, a look of joy appeared on her face.
The kanji 悦 combines 忄 (heart) with 兌 (exchange, pleasure), suggesting a heart filled with pleasure. The reading えつ is the on'yomi.