Frax glossary

Last reviewed

Frax has its own vocabulary, and the 2025 rebrand added a few synonyms to keep track of. Every term below is defined in one or two sentences. Where a definition touches something that changes over time, the relevant page has the live detail.

AMO
Algorithmic Market Operations Controller: an autonomous smart contract that deploys protocol collateral into strategies without changing the stablecoin's peg.
BAMM
Borrow Automated Market Maker: a borrowing and lending module built on top of Fraxswap that can operate without external oracles.
Collateral ratio
The share of each stablecoin unit backed by held collateral. Frax governance voted to move FRAX to full (100%) collateralization.
FIP
Frax Improvement Proposal: the formal document used to propose, discuss and vote on changes to the protocol.
Flox
Fraxtal's blockspace incentive program that rewards users and developers for spending gas and interacting with contracts on the network.
FPI
The Frax Price Index stablecoin, pegged to a basket of consumer goods based on the US CPI rather than to a single dollar.
FRAX
The protocol's original USD-pegged stablecoin. Under the 2025 North Star rebrand the flagship stablecoin is branded frxUSD, while the name FRAX moves to the renamed governance and gas token.
Frax Finance
A decentralized stablecoin protocol and DeFi ecosystem launched in December 2020. It now spans the FRAX/frxUSD stablecoins, frxETH liquid staking, lending, an AMM and the Fraxtal layer-2 network.
Fraxferry
An optimistic transfer protocol used to move Frax-based tokens between chains.
Fraxlend
Frax's permissionless lending market, organized as isolated pairs of ERC-20 assets so risk in one market does not spill into others.
Fraxswap
Frax's native automated market maker, based on a Uniswap V2 design, with built-in time-weighted average market maker (TWAMM) orders.
Fraxtal
Frax's layer-2 rollup built on the Optimism OP Stack. It is EVM-compatible and is central to the protocol's scaling plans.
frxETH
Frax Ether, a token that tracks the price of ETH one to one and serves as the base liquid-staking asset in the Frax ETH system.
frxUSD
The flagship Frax stablecoin brand introduced in 2025, designed for direct fiat redemption through regulated partners. Verify current backing and redemption terms in the official documentation.
FXB
Frax Bonds: zero-coupon, bond-like tokens that are auctioned below par and redeem for one stablecoin unit at maturity.
FXS
Frax Shares, the long-standing governance and value-accrual token. The North Star proposal renames FXS to FRAX and makes it the gas and staking token of Fraxtal.
sFRAX
An ERC-4626 staking vault that distributes part of the protocol's yield to depositors of the Frax stablecoin.
sfrxETH
Staked frxETH, an ERC-4626 vault. Its exchange rate against frxETH rises as validator rewards accrue, so it represents a growing claim on the vault's frxETH.
TWAMM
Time-Weighted Average Market Maker: a mechanism that splits a large order into many tiny trades executed continuously over time to reduce price impact.
veFXS
Vote-escrowed FXS. Users lock FXS for a chosen period to receive non-transferable voting power; longer locks grant more weight. Being renamed veFRAX alongside the token rebrand.

Want these terms in context rather than alphabetical? Start with what Frax is, then how it works and the token map.