A spending policy requiring more than one approved key.
Multisignature meaning
Multisignature, often shortened to multisig, lets a Bitcoin output require a threshold of signatures. A 2-of-3 setup, for example, can be spent with any two of three specified keys. This can remove one device as a single point of failure.
How it works in Bitcoin
The spending condition is encoded in the output's script or committed through a modern script construction. Wallets must preserve the keys and enough policy or descriptor information to reconstruct and spend the funds.
A simple example
A company can place three keys with separate officers and require any two to approve a treasury payment. One lost key does not stop spending, while one stolen key is insufficient.
Why Multisignature matters
Wallet terms describe key control, signing and recovery rather than coins stored inside an application. The distinction becomes critical during backup or device failure.
What people often get wrong
Multisig adds coordination, fee, privacy, and recovery complexity. Test the complete backup and recovery process before depositing an important amount.
Quick checks before using the term
- Who controls the spending keys?
- How would recovery work after a lost device?
- Has the backup been tested without exposing it?
Apply these questions to the concrete example above. A precise answer is more useful than repeating the definition without naming the actor, rule or failure path.
Check the primary reference
This entry is written in plain English, but the technical source is available when you need exact protocol detail.
Bitcoin Developer Guide: Wallets ↗