Glossary

Clear, standalone definitions for every concept behind Spield — from Principal Tokens and implied APY to Blend, Soroban, and real-world assets.

Yield tokenization

Principal Token (PT)

A Principal Token (PT) is a token that represents the principal of a yield-bearing deposit and redeems 1:1 for the underlying asset at maturity, functioning like an on-chain zero-coupon bond.

Yield Token (YT)

A Yield Token (YT) is a token that represents all the yield a deposit will generate between now and maturity.

Yield tokenization is the process of splitting a yield-bearing asset into two separate, tradable tokens: a Principal Token (PT) that redeems for the principal at maturity, and a Yield Token (YT) that captures the yield until maturity.

Implied APY

Implied APY is the annualized fixed yield the market is currently pricing into a yield-tokenized asset, derived from the prices of its Principal Token and Yield Token.

Underlying APY

Underlying APY is the actual, variable annual yield a deposit is currently earning from its yield source (such as a lending market), typically shown as a recent moving average.

Time-Decay AMM

A time-decay AMM is an automated market maker designed to trade Principal Tokens, whose pricing curve accounts for the fact that a PT converges to par value as maturity approaches.

Fixed income

Zero-Coupon Bond

A zero-coupon bond is a bond that pays no periodic interest and is instead sold below its face value, returning full face value at maturity.

Maturity

Maturity is the date on which a fixed-income instrument expires and pays out.

Fixed Income

Fixed income is a class of investments that pay a predictable, predetermined return over a set period, such as bonds and fixed-rate deposits.

Stellar & Blend

Blend Capital

Blend Capital is the primary decentralized lending protocol on Stellar, where users supply assets like USDC to earn a variable yield and borrowers post collateral to take loans.

bToken (bRate)

A bToken is the receipt token Blend Capital gives a supplier in exchange for a deposit, and its exchange rate (the bRate) rises over time as interest accrues.

Soroban

Soroban is the smart-contract platform on the Stellar network, letting developers write on-chain programs in Rust.

Stellar

Stellar is a fast, low-cost, open-source blockchain built for payments, asset issuance, and — since the launch of Soroban smart contracts — decentralized finance.

Real-world assets

Tokenized Treasuries

Tokenized treasuries are blockchain tokens that represent ownership of U.S.

Real-World Asset (RWA)

A real-world asset (RWA) in crypto is a traditional off-chain asset — such as a Treasury bill, bond, real estate, or invoice — represented as a blockchain token backed by the underlying asset held in custody.