Glossary
Validator
A node in a proof-of-stake network that proposes and attests to blocks. To participate it must lock up the protocol's staking minimum and risk slashing.
In a proof-of-stake network, a validator is the equivalent of a miner: the node that produces and signs blocks. Becoming one requires locking a minimum stake (32 ETH on Ethereum, varies elsewhere) and running highly available infrastructure.
Validators are paid in newly issued tokens and in priority fees, and they can be slashed for double-signing or extended downtime. Large operators often run hundreds or thousands of validators behind a single key-management setup.