A DeFi aggregator is a platform that consolidates data and services from multiple decentralized finance protocols into a single interface. It allows users to access the best lending, borrowing, trading, and yield farming options without switching between platforms. DeFi aggregators optimize returns by routing transactions through the most profitable paths across protocols like Uniswap, Aave, and Curve. These tools enhance user experience, reduce gas fees, and simplify DeFi interactions. They are essential for users seeking efficient, real-time access to decentralized financial opportunities.