roundelay vs song

roundelay and song both are nouns.

Word	Noun	Adjective	Verb	Adverb
roundelay	Yes	No	No	No
song	Yes	No	No	No

As nouns, song is a hypernym of roundelay; that is, song is a word with a broader meaning than roundelay:

Other hypernyms of roundelay include vocal.

roundelay (noun)	song (noun)
a song in which a line or phrase is repeated as the refrain	the act of singing
	a short musical composition with words
	the characteristic sound produced by a bird
	a distinctive or characteristic sound
	a very small sum