Which term refers to several notes sung to one syllable?

The term that refers to several notes sung to one syllable is "melismatic." In this vocal technique, a single syllable of text is elaborated with multiple pitches, creating a flowing and decorative musical line. This style is often found in various forms of music, particularly in genres that emphasize expressive singing, such as opera, and in certain types of chant and traditional music.

Melismatic singing contrasts with syllabic singing, where each syllable is matched to a single note. While strophic refers to a song structure where verses or stanzas are repeated, and verbal is not a recognized term in this context, melismatic effectively captures the essence of multiple notes corresponding to one syllable, making it the correct choice.