Validator
A validator is a node that actively secures a proof-of-stake network: it proposes and confirms blocks, earns rewards, and loses ("gets slashed") stake if i
A validator is a node that actively secures a proof-of-stake network: it proposes and confirms blocks, earns rewards, and loses (“gets slashed”) stake if it behaves badly. Anyone who meets the stake requirement can run one — or small holders can delegate to an existing validator.
Why it matters
Who runs the validators — and how evenly the stake is spread across them — is a direct measure of decentralization. A large validator set with balanced stake is harder to compromise than a system where a few operators control the majority.