悅

A compound ideograph composed of:

心 — “heart; mind,” representing emotions;

兌 — originally meaning “to exchange” or “to open,” also associated with pleasant expression or smiling.

Together, the character conveys the idea of a heart filled with joy or delight.

희열 (喜悅) — joy; delight

열락 (悅樂) — pleasure; enjoyment

The character is often used in literary or formal contexts to express deep or refined joy, rather than casual happiness.
Related characters: 喜 — joy; happiness

樂 — pleasure; enjoyment

歡 — joy; delight