lament vs song

lament and song both are nouns.

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

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

lament: a song or hymn of mourning composed or performed as a memorial to a dead person
song: a short musical composition with words

Other hypernyms of lament include vocal.

lament (noun)	song (noun)
a mournful poem; a lament for the dead	the act of singing
a song or hymn of mourning composed or performed as a memorial to a dead person	a short musical composition with words
a cry of sorrow and grief	the characteristic sound produced by a bird
	a distinctive or characteristic sound
	a very small sum

lament (verb)	song (verb)
regret strongly
express grief verbally