An Ethereum entity that adds the next block of transactions to the blockchain. It used to be a "miner" but changed to a "proposer" in 2022 when Ethereum switched from proof-of-work to proof-of-stake. Miners became validator proposers and validators became validator attesters. However, there are seven years' worth of books and articles about "Ethereum miners," which means the "miner" term may linger for the time being. See
Ethereum 2.0 and
crypto mining.