1: a prominent public figure, socialite, or generally someone who is doing well for themselves and happens to be balling out of control as they should, why not?
2: a fancy top-of-the-line product or service — this can be anything from an audiophile high-end stereo system, a hypercar, a high-performance computing application, etc.
3: anything that's huge in terms of size e.g., a mansion, a private plane, a superyacht, etc.
Synonyms for the 1st meaning
Mbinga (or mbingaldo)
Muchangazi (slang for changamire)