When we call someone charming, we are — etymologically — accusing them of witchcraft. The word charm entered English around 1300 from Old French charme, meaning 'magic spell' or 'incantation'.
The Old French itself came from Latin carmen, which meant 'song' or 'verse', from the verb canere 'to sing'. The connection is ancient and literal: magic was performed through singing. A charm was a song with supernatural power — a formula of words, chanted in the right rhythm, that could heal, curse, or compel.
The Proto-Indo-European root *kan- simply meant 'to sing'. From it grew Latin canere (giving us chant, canticle, and cantata), and through the magical branch, carmen and charm.
The transformation from 'spell' to 'attractiveness' happened gradually during the 17th century. To be charmed shifted from supernatural compulsion to willing delight. But the metaphor persists: we still speak of being 'enchanted' by beauty, 'spellbound' by a performance, 'captivated' by a smile. The language remembers that attraction was once understood as a form of magic.