Glossary

Air-gapped - a security setup where the signing device has no network connection. Polkadot Vault runs on an offline phone; communication happens only through QR codes.

Alpha - a subnet-specific token on the Bittensor network. Each subnet has its own alpha token that can be staked.

Coldkey - the primary account key in Bittensor that holds TAO and controls staking. In the wallet, this corresponds to a software or Ledger account.

dApp - a decentralized application running in a browser that connects to the wallet to read accounts or request transaction signatures.

Extrinsic - a signed transaction submitted to the Bittensor/Substrate blockchain. Transfers, staking operations, and proxy calls are all extrinsics.

Hotkey - a secondary key in Bittensor used for mining and validation duties. Staking is done from a coldkey to a hotkey on a specific subnet.

MeV Shield - a Bittensor-specific signed extension that protects transactions from miner extractable value attacks. The wallet detects and displays MeV Shield status during signing.

Multisig - a multi-signature account that requires a minimum number of signatories (the threshold) to approve any operation. No single party can act alone.

Passkey - a biometric or hardware-backed authentication method using WebAuthn. The wallet uses the PRF (pseudo-random function) extension to derive a key that wraps the vault session.

Polkadot Vault - a mobile app (formerly Parity Signer) that turns a phone into an air-gapped signing device. The wallet communicates with it by displaying and scanning QR codes. See Polkadot Vault accounts.

Popup - the default display mode where the wallet opens as a small overlay window attached to the browser toolbar.

Proxy - a Substrate mechanism that lets one account (the delegate) act on behalf of another (the real account) without having access to the real account's private key. Proxies are scoped by type (e.g., Any, Staking, Governance).

Pure Proxy - an on-chain identity with no private key of its own. It exists only as a proxy target, controlled entirely by its proxy delegates. Losing all delegates means permanent loss of access.

Signatory - one of the members of a multisig account. Each signatory holds a key and can approve or initiate multisig operations.

Side Panel - an alternative display mode where the wallet opens as a persistent panel on the side of the browser window. Required for passkey enrollment.

SS58 - the address encoding format used by Substrate-based chains. Bittensor uses SS58 with prefix 42.

Service Worker - the background process in a Manifest V3 browser extension. It handles vault state, signing, RPC calls, and message routing. It can be suspended and restarted by the browser at any time.

Staking - locking TAO on a specific subnet by delegating it to a hotkey. Staked TAO earns rewards but cannot be transferred until unstaked.

Subnet - an independent network within Bittensor that runs a specific machine learning task. Each subnet has its own set of validators and miners.

TAO - the native token of the Bittensor network, denoted with the tau symbol. Used for staking, transfers, and paying transaction fees.

Threshold - the minimum number of multisig signatories required to approve an operation. For example, a 2-of-3 multisig has a threshold of 2.

UOS - Universal Offline Signing. The QR code protocol used between the wallet and Polkadot Vault to exchange transaction payloads and signatures.

Vault - the encrypted container that stores all wallet data at rest - accounts, settings, permissions, and network-scoped data. Encrypted with PBKDF2 + AES-GCM. See Security Model for details.