ecstasy vs seventh heaven

ecstasy and seventh heaven both are nouns.

Word	Noun	Adjective	Verb	Adverb
ecstasy	Yes	No	No	No
seventh heaven	Yes	No	No	No

As nouns, seventh heaven is a hypernym of ecstasy; that is, seventh heaven is a word with a broader meaning than ecstasy:

Other hypernyms of ecstasy include bliss, blissfulness, cloud nine, walking on air.

ecstasy (noun)	seventh heaven (noun)
street names for methylenedioxymethamphetamine	a state of extreme happiness
a state of being carried away by overwhelming emotion
a state of elated bliss