septet vs assemblage

septet and assemblage both are nouns.

Word	Noun	Adjective	Verb	Adverb
septet	Yes	No	No	No
assemblage	Yes	No	No	No

As nouns, assemblage is a hypernym of septet; that is, assemblage is a word with a broader meaning than septet:

Other hypernyms of septet include gathering.

septet (noun)	assemblage (noun)
a musical composition written for seven performers	the social act of assembling
seven people considered as a unit	a system of components assembled together for a particular purpose
a set of seven similar things considered as a unit	a group of persons together in one place
seven performers or singers who perform together	several things grouped together or considered as a whole
the cardinal number that is the sum of six and one