Crypto glossary, A to Z
Short, sourced definitions of the words you will meet in every other guide. Each entry has an example and links onward.
A
B
Block height
The position of a block in the chain, counted as the number of blocks before it; the genesis block is height 0.
C
Cold wallet
A crypto wallet whose private keys are kept on a device that is not connected to the internet.
Confirmation
One block added on top of a transaction: the first when it is included in a block, then one more for each later block.
D
DEX (decentralized exchange)
A decentralized exchange: smart contracts that let people swap tokens from their own wallets, with no company holding their funds.
G
Gas
The unit that measures the computational work an Ethereum transaction needs; the fee is gas used times a price per gas, paid in ETH.
H
L
M
Market capitalization
The value of an asset’s supply at the current market price: price per unit multiplied by the number of units counted.
Mempool
A node’s holding area for valid transactions that have not yet been included in a block.
N
Node
A computer running blockchain software that connects to other computers to relay and check transactions and blocks.
P
Private key
A secret number that signs transactions and therefore controls the crypto linked to it.
S
Satoshi (sat)
The smallest unit of bitcoin recorded on the blockchain: one hundred-millionth of a bitcoin, or 0.00000001 BTC.
Seed phrase
A list of 12 to 24 words that encodes the random number from which a wallet creates all of its private keys.
Slippage
The difference between the price you expect when you place a trade and the price at which it actually executes.
Smart contract
A program stored at its own address on a blockchain such as Ethereum, which runs exactly as written when a transaction calls it.
Stablecoin
A crypto token designed to keep a stable value against a reference asset, usually the US dollar.
Staking
Locking up a proof-of-stake network’s coins as a security deposit to help validate blocks, earning rewards and risking penalties.
U
UTXO (unspent transaction output)
An unspent transaction output: a piece of bitcoin received in an earlier transaction that has not yet been spent.
W
Whale
Informal name for a holder controlling a very large amount of a cryptocurrency; no industry-wide size threshold exists, though data providers set their own.
Wrapped token
A token that represents another asset one-for-one, issued by a contract or custodian that holds the original, such as WETH for ETH.