From the great knowledge base (kek?) known as Wikipedia, which is usually accurate on etymology:

The word soviet is derived from the Russian word sovet (Russian: совет), meaning "council", "assembly", "advice",[s] ultimately deriving from the proto-Slavic verbal stem of vět-iti ("to inform"), related to Slavic věst ("news"), English "wise", the root in "ad-vis-or" (which came to English through French), or the Dutch weten ("to know"; cf. wetenschap meaning "science"). The word sovietnik means "councillor".

So a "Soviet Union" (as opposed to the socialist "USSR") would essentially be a union of the wise or a group of the informed. If Putin wants to set up THAT kind of union, I say: where do we sign up?