Yield Aggregator

A protocol (often structured as 'vaults') that automates DeFi yield strategies on depositors' behalf — deploying funds, auto-compounding rewards, and sometimes rotating between opportunities — sharing gas costs and expertise (Yearn is the pioneer). The convenience hides layered risk: the vault deploys into other protocols, so you inherit its own plus every underlying protocol's smart-contract risk, and an attractive APY may be unsustainable token emissions rather than real fees/interest.