This is the 12002nd most frequent Korean word.
녹이다
"녹이다" means "to melt" or "to dissolve."
Here, "녹이다" indicates causing the ice to melt by applying warm water, emphasizing the action of melting something.
얼음을 따뜻한 물에 녹였어요.
I melted the ice in warm water.
In this sentence, "녹이다" refers to the act of chocolate transitioning from a solid state to a melted state within the mouth, showing a natural melting process.
초콜릿이 입안에서 녹아요.
The chocolate melts in the mouth.
Here, "녹이다" is used metaphorically to describe the emotional impact of the song, softening or touching people's hearts.