melisma

1. (music, countable) A passage of several notes sung to one syllable of text.Examples: "A choir sang one of the Lamentations of Jeremiah. The mournful melisma accompanied the slow procession to the palace built by Herod the Great, at present untenanted."; "At the top of the hill in the archway of the main house, an eyeless old man sat on a bucket, scratching at a two-stringed gourd, warbling weird melismas on a madman's text."countable

2. (music, uncountable) The use of such passages.Examples: "A subsequent generation of singers, including Ms. Aguilera, Jennifer Hudson and Beyoncé, built their careers around melisma."uncountable