heptasyllable vs verse

heptasyllable and verse both are nouns.

Word	Noun	Adjective	Verb	Adverb
heptasyllable	Yes	No	No	No
verse	Yes	No	Yes	No

As nouns, verse is a hypernym of heptasyllable; that is, verse is a word with a broader meaning than heptasyllable:

Other hypernyms of heptasyllable include verse line.

heptasyllable (noun)	verse (noun)
a word or line of verse of seven syllables.	a piece of poetry
	a line of metrical text
	literature in metrical form

heptasyllable (verb)	verse (verb)
	familiarize through thorough study or experience
	compose verses or put into verse