Crypto Glossary A to Z

Entry last verified July 2026.

Address. The destination string for a transfer, derived from a public key. Safe to publish.

Airdrop. Tokens distributed to wallets, usually to bootstrap users. Also a common scam format.

Allowance. Permission granted to a contract to move a specific token from your address. Does not expire.

AMM. Automated market maker. A formula-based pricing mechanism used by decentralised exchanges instead of an order book.

Base fee. On Ethereum, the protocol-set minimum fee per unit of gas. Burned rather than paid to validators.

Block. One batch of transactions added to the chain.

Block explorer. A website for reading chain data: transactions, addresses, contracts.

Bridge. Infrastructure for moving value between chains. Historically among the most exploited components in crypto.

Cold storage. Keys held on a device that never connects to the internet.

Confirmation. A block added on top of the one containing your transaction.

Consensus mechanism. The rules by which a network agrees on a single history.

Custodial. An arrangement where someone else holds the keys.

DEX. Decentralised exchange. A contract that swaps assets directly from your wallet.

Dust. An amount so small that moving it costs more than it is worth.

Finality. The point at which a transaction can no longer be reversed.

Fork. A change to the rules. Soft forks are backwards-compatible; hard forks are not.

Gas. A measure of computational work required by a transaction.

Gas limit. The maximum gas you authorise. Exceeding it causes failure and you still pay.

Halving. The scheduled reduction of Bitcoin’s block subsidy, approximately every four years.

Hot wallet. A wallet whose keys are on an internet-connected device.

Impermanent loss. The shortfall a liquidity provider takes versus simply holding, when pooled asset prices diverge.

Layer 1. A base blockchain.

Layer 2. A network built on a layer 1 that processes transactions and settles back in batches.

Liquidation. Forced closure of a collateralised position when collateral falls below a threshold.

Liquidity. How much can be traded without moving the price.

Mempool. A node’s set of transactions broadcast but not yet included in a block.

MEV. Value extractable by whoever controls transaction ordering in a block.

Multisig. A wallet requiring several keys to authorise a transaction.

Node. A computer holding a copy of the chain and validating new blocks.

Nonce. A counter ensuring transactions from an address execute in order.

Oracle. A service supplying external data, usually prices, to a contract.

Private key. The secret that authorises spending. Never shared.

Proof of stake. Block production rights allocated by staked capital, with penalties for misbehaviour.

Proof of work. Block production rights won by expending computation.

Public key. Derived from the private key. Addresses are derived from it. Safe to publish.

Reorg. When the network discards recent blocks in favour of a different version of history.

Rollup. A layer 2 design: execute off-chain, post data or proofs on-chain.

Rug pull. A project’s creators taking the money and abandoning it.

Seed phrase. Twelve or twenty-four words that regenerate all of a wallet’s keys.

Slashing. Destruction of part of a validator’s stake as a penalty.

Slippage. The difference between expected and received price on a trade.

Smart contract. A program on a blockchain that executes as written and cannot be edited afterwards.

Spread. The gap between the best bid and the best offer.

Staking. Locking assets as collateral to help secure a proof-of-stake network.

Stablecoin. A token designed to hold a fixed value, usually one US dollar.

TVL. Total value locked in a protocol. A popularity measure, not a safety one.

Unbonding period. The delay between requesting an exit from staking and receiving the assets.

Validator. A participant proposing and attesting to blocks on a proof-of-stake network.

Wallet. Software or hardware managing keys and constructing transactions. It does not hold coins; the chain does.

Where terms are defined authoritatively

Protocol documentation for protocol terms, and the improvement proposal for anything with a number attached. Market terms vary by venue, and the definitions used in a platform’s own fee schedule are the ones that apply to your account. Those are published by venues including venues where the asset is listed for retail purchase.