What does DeFi mean in crypto?

DeFi is an acronym for decentralized finance. It refers to the collections of applications and websites that offer services formerly provided by banks and financial institutions. DeFi platforms, by contrast, offer these services on a decentralized network powered by the blockchain which removes the problems of redundant third parties, slow processing time, and the issue of trust which has been violated time and again by centralized institutions and government. There are grave problems like reverse repos that make common people a gambling ground for financial institutions, and insider activities to mention a few.

DeFi, or decentralized finance, is a relatively new financial technology coined in 2018 that has been revolutionizing the way we operate with money. So, it's neither a cryptocurrency nor a platform - it's just a different financial technology consisting for many cryptocurrencies, platforms, and functionalities. To understand it better, remember that our current financial system, which is based on fiat money is called TradFi (traditional finance). Instead of using fiat money, DeFi seeks to revolutionize the way we handle transactions by implementing blockchain technology.