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

Following the hack, the security council of the Arbitrum blockchain froze about $71 million in stolen funds that the attackers had moved onto the blockchain.

From The Wall Street Journal • Apr. 29, 2026

"Lots of folks participating in Polymarket are not identified precisely because of the blockchain technology," Professor Joshua Mitts from Columbia Law School told the BBC.

From BBC • Apr. 28, 2026

The earnings that a mystery trader scored from a $120 Polymarket bet on the weather, according to a blockchain analytics firm.

From The Wall Street Journal • Apr. 23, 2026

The two companies plan to collaborate on tokenized real-world assets, representing an ownership stake in physical bullion traded on Tether’s blockchain technology that leverages Gold.com’s existing CyberMetals digital investing accounts network.

From Barron's • Apr. 16, 2026

This was a popular strategy in late 2017 and early 2018, as businesses sought to hop on the blockchain bandwagon.

From MarketWatch • Apr. 15, 2026