Glossary
USDC off-ramp glossary.
A direct reference for the terms you will see in USDCtoFiat, ZKP2P, payment proof, and Base contract settlement.
01
Core protocol terms
| Term | Definition |
|---|---|
| ZKP2P | The protocol that coordinates fiat payment proof and onchain asset release for peer-to-peer ramps. |
| USDCtoFiat | A seller-focused product for selling native USDC on Base for fiat through supported payment apps. |
| Maker | The seller who deposits USDC liquidity and receives fiat. |
| Taker | The buyer who pays fiat and receives USDC from a seller deposit. |
| Deposit | A seller's locked USDC plus payment method, currency, identifier, size limits, and rate. |
| Intent | A buyer order against a deposit. It reserves part of the deposit while the buyer completes payment. |
| Intent hash | The unique identifier for a buyer order, used to bind payment proof to the correct fill. |
| EscrowV2 | The Base contract that holds seller USDC until withdrawal or verified release. |
| OrchestratorV2 | The Base contract path for signaling intents, fulfillment, cancellation, and release coordination. |
02
Verification terms
| Term | Definition |
|---|---|
| PaymentAttestation | An EIP-712 signed statement that a fiat payment matched a specific intent. |
| UnifiedPaymentVerifierV2 | The onchain verifier that checks the payment attestation, snapshot values, and nullifier. |
| Nullifier | A one-time marker derived from payment evidence to stop the same payment being used twice. |
| Payee details hash | A hash of the seller's payout identifier, used to bind payment destination without posting the handle onchain. |
| TEE | Trusted execution environment. ZKP2P V3 uses AWS Nitro Enclaves for supported payment verification flows. |
| zkTLS | A proof technique for authenticating TLS-served web data. ZKP2P used zkTLS historically and still keeps the concept in the broader proof vocabulary. |
| Seller Autopilot | A seller-side automated release flow where encrypted seller credentials let the enclave detect inbound payments for supported methods. |
03
Seller operation terms
| Term | Definition |
|---|---|
| Spread | Seller margin over a reference FX rate. |
| Oracle-tracked rate | A rate that follows market data with a configured spread or floor instead of staying fixed forever. |
| Manual release | A seller-triggered release used only when automated proof fails but the seller independently verifies payment. |
| Trusted taker | A buyer wallet allowed to fill a restricted deposit. |
| Private OTC order | A deposit with a whitelist hook, share link, and one approved buyer wallet. |
| Delegate fee | The buyer-side manager fee on delegated fills. It is not deducted from seller fiat proceeds. |
| Referrer fee | An optional buyer-side fee in some flows, separate from the seller's fiat proceeds. |
Keep exploring
Common questions
What is the simplest way to explain USDCtoFiat?
USDCtoFiat lets a seller lock USDC on Base and receive fiat from a buyer through a supported payment app. USDC releases only after the buyer's payment is verified.
What term should I search if I want the contract flow?
Search for EscrowV2, OrchestratorV2, intent hash, PaymentAttestation, and UnifiedPaymentVerifierV2.