Plain meaning
Start with the shortest useful explanation before going deeper.
A mechanism where staked SOL is represented by a transferable token (LST) that accrues staking rewards while remaining usable in DeFi. Instead of locking SOL with a validator, users deposit into a liquid staking pool and receive tokens like mSOL (Marinade), jitoSOL (Jito), or bSOL (BlazeStake). LSTs typically appreciate against SOL at the staking APY.