blockchain

American  

[blok-cheyn] / ˈblɒkˌtʃeɪn /

noun

Computers.

1. a structure used for a distributed or shared database consisting of discrete blocks of data, with each new block secured and connected to earlier ones by cryptography: used to create digital ledgers for cryptocurrency systems, among other things.

   Several schools now offer courses in the technology behind blockchain.

   Under the scheme, farmers would add information about their produce to a blockchain database that could quickly pinpoint contamination.

2. a distributed or shared database created and populated using a structure consisting of discrete blocks of data, with each new block secured and connected to earlier ones by cryptography.

   Once the transaction gets verified, it's recorded in the blockchain.

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Etymology

Origin of blockchain

First recorded in 2010–15; block ( def. ) + chain ( def. )

Explanation

A blockchain is a shared computer database that's mainly used for keeping records of cryptocurrency transactions. When someone buys or sells Bitcoin, they use a blockchain to safely record the details. A blockchain works like a shared spreadsheet, with data entered into separate cells or columns. The special thing about blockchain is that once information is put into each block, it can't be changed, making it an extremely secure way to store data. The name blockchain comes from the blocks of data, linked together in chains through cryptography.

Example Sentences

BTQ Technologies is developing a separate version of the bitcoin blockchain that it claims will be safe against quantum computing, and it plans to launch its own cryptocurrency in the future.

From MarketWatch • Mar. 31, 2026

This is because Polymarket uses blockchain technology that allows users to place bets anonymously.

From Salon • Mar. 25, 2026

Tokenized cash represents currency or bank deposits as digital tokens on a distributed ledger or blockchain, promising instant, programmable settlements.

From The Wall Street Journal • Mar. 24, 2026

Last week, the Securities and Exchange Commission approved Nasdaq’s proposal to allow investors to trade certain high-volume stocks either as traditional shares or as tokens on the blockchain, all within Nasdaq’s existing exchange.

From The Wall Street Journal • Mar. 24, 2026

Subscriptions and services revenue, which includes custodial fees and staking—locking up assets for a fee to verify blockchain transactions—exceeded transaction revenue for the first quarter ever.

From Barron's • Mar. 20, 2026