roulade vs melodic line

roulade and melodic line both are nouns.

Word	Noun	Adjective	Verb	Adverb
roulade	Yes	No	No	No
melodic line	Yes	No	No	No

As nouns, melodic line is a hypernym of roulade; that is, melodic line is a word with a broader meaning than roulade:

Other hypernyms of roulade include air, line, melodic phrase, melody, strain, tune.

roulade (noun)	melodic line (noun)
(music) an elaborate run of several notes sung to one syllable	a succession of notes forming a distinctive sequence
a dish consisting of a slice of meat that is rolled around a filling and cooked