Extravagant is an adjective that means expensive, excessive, and over the top. A modest chandelier in your dining room is normal. But crystal-studded walls and gold-plated goblets? That's a bit extravagant.
If you’re prone to lavish behavior or spending, you’re extravagant. It’s an adjective associated with extremes, sometimes even to the point of absurdity. Fees at a bank can be extravagant, and so can a person who insists on drinking only bottled French mineral water out of a golden chalice. Remember that the only ‘e’ is at the beginning — the remaining three vowels are all ‘a.’