단풍이 · 단풍을
autumn leaves, fall foliage; maple
Example
가을에 설악산에 가면 단풍이 정말 예뻐요.
If you go to Seoraksan in the fall, the autumn leaves are really beautiful.
Word parts
단 red+풍 maple
Literally 'red maple'; now it means any leaves turning color.
Related words