There is a meaningful difference. A ponzi scheme involves: schemer takes money from Mr. A. At a later date he takes money from Mr B. He gives some of the money

There is a meaningful difference. A ponzi scheme involves: schemer takes money from Mr. A. At a later date he takes money from Mr B. He gives some of the money from Mr. B to Mr A, and tells Mr. A that it's "returns". He tells Mr B. all is fine. Then Mr C comes along and his money is given to Mr. A and Mr. B, as "returns". This continues. It's a very specific type of fraud. Most fraud isn't a ponzi, just like every injury isn't a broken arm. It's silly to go around calling all injuries a broken arm.