달 derives from Old Korean *tʌr, cognate with proto-Koreanic roots relating to cycles and brightness. The same word covers both "moon" and "month" — a natural pairing found in many languages, since months were originally measured by lunar cycles.

The moon holds deep cultural significance in Korea. 추석 (Chuseok), the major harvest festival, is timed to the full moon of the 8th lunar month. On that night, families gather outdoors to admire the 보름달 (full moon) and give thanks. The moon also appears constantly in Korean poetry and folk songs as a symbol of longing, especially for faraway loved ones. Note the handy double meaning: 이 달 means "this month," and 달빛 means "moonlight."