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Crypto Glossary
1,343 crypto, Web3, and DeFi terms — plain-English definitions from the BlockInsider editorial desks.
O
- OCO Order
- OHM Fork
- ORC-20 Tokens
- Odysee
- Off-Chain
- Off-Chain Governance
- Off-Chain Transaction
- Off-Ledger Currency
- Office of the Comptroller of the Currency (OCC)
- Offline Signing Orchestrator (OSO)
- Offline Storage
- Offshore Account
- On-Balance Volume (OBV)
- On-Chain
- On-Chain Governance
- On-Ledger Currency
- Onchain Fiat
- One Cancels the Other Order (OCO)
- Online Storage
- Open Interest
- Open Source
- Open-Source Software (OSS)
- Open/Close
- OpenSea
- Opera Mainnet (Fantom)
- Operating System (OS)
- Optimistic Oracle
- Optimistic Rollup
- Option
- Options Market
- Oracle
- Oracle Manipulation
- Order Book
- Ordinals
- Orphan
- Orphan Block
- Ouroboros Praos
- Over-Collateralization
- Over-the-Counter (OTC) Trading
- Overbought
- Oversold
