What does DeFi (decentralized finance) mean?

Financial services — trading, lending, borrowing — provided by smart contracts on a blockchain instead of by banks or brokers.

Instead of trusting an intermediary that could freeze you out, you interact directly with inspectable code. A decentralized exchange where users swap tokens through a contract is a canonical example.

Go deeper:

• Decentralized finance — Wikipedia — diagrams the layered DeFi stack.