eightsome vs octet

eightsome and octet both are nouns.

Word	Noun	Adjective	Verb	Adverb
eightsome	Yes	No	No	No
octet	Yes	No	No	No

As nouns, eightsome and octet are synonyms defined as:

Other synonyms of eightsome include octette.

eightsome (noun)	octet (noun)
a Scottish reel for eight dancers	a musical composition written for eight performers
eight people considered as a unit	eight people considered as a unit
	a set of eight similar things considered as a unit
	eight performers or singers who perform together
	the cardinal number that is the sum of seven and one