Almost everything can be defined as a ponzi scheme

Ponzi schemes are named after Charles Ponzi, the American fellow (where else?) who "popularised" them back in the 1920s. In simplistic terms, Ponzi schemes work on the principle of hypnotising gullible sheeple into investing money in a generally ill-defined "business enterprise", promising larger-than-life returns that are usually paid out to the initial "investors" using money mostly acquired from later "investors".