Synergy is an interaction or cooperation giving rise to a whole that is greater than the simple sum of its parts. The term synergy comes from the Attic Greek word συνεργία synergia meaning working together.
An opus is a created work, usually musical in nature.
A common usage of opus is with the term magnum opus which refers to one's greatest work, musical or otherwise
https://www.vocabulary.com/dictionary/opus
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