IPA: /ˈsoʊl.fəli/
KK: /ˈsoʊl.fəl.i/
In a way that expresses deep feelings or emotions, often related to music or art.
She sang soulfully, moving everyone in the audience to tears.
Soulfully → It is formed from "soul" (from Old English *sāwol*, meaning the spiritual or immaterial part of a human being) and "-fully" (meaning in a manner full of). The word "soulfully" means in a manner that is full of soul or deep feeling.
Think of the word 'soul' representing deep emotions and 'fully' meaning in a complete way — so 'soulfully' describes doing something with deep emotion.