A flash loan is an uncollateralized loan borrowed and repaid within the same transaction.
If repayment fails, the whole transaction reverts. Flash loans enable arbitrage and sometimes complex exploits.
In research workflows, Flash loan is usually interpreted with DeFi, Exploit, Automated market maker, and Arbitrage rather than as a standalone signal. Smart-contract, oracle, and governance risks are part of the product. Yield without understanding the mechanism is usually underpriced risk.