A seed phrase is a human-readable backup, usually 12 or 24 words, that can restore a wallet's keys.
Anyone with the seed phrase can recreate the wallet and steal funds. Store it offline and never type it into random websites.
In research workflows, Seed phrase is usually interpreted with Private key, Crypto wallet, Cold wallet, and Phishing rather than as a standalone signal. Operational security mistakes are irreversible on most public chains. Verify networks and destinations before large transfers.