Glossary

Glossary — the words of bitcoin custody, explained simply

Twenty terms you will come across while securing your bitcoin and preparing access for your loved ones. No needless jargon.

Bitcoin: A network and a digital currency with no central authority. Bitcoins exist only on the blockchain; what you "hold" are the keys that let you move them. Lose the keys and you lose access — no one can recreate them.
Private key: The secret that authorises a transaction. Whoever holds it can move the funds, with no password or further approval. All of security comes down to knowing where the keys are and who can use them.
Recovery phrase (seed): A sequence of 12 or 24 words that rebuilds every key in a wallet. It is the ultimate backup: anyone who reads it can take everything, anyone who loses it recovers nothing. Never photograph it, never type it into a connected computer, never store it in the cloud.
Passphrase (the "25th word"): An extra secret, chosen by you, combined with the recovery phrase to create a separate wallet. It protects against theft of the phrase alone, but adds a point of failure: forget it and the wallet is inaccessible, even with the 24 words. It must be backed up separately.
Hardware wallet (cold wallet): A small device that keeps your keys offline and signs transactions without exposing them to the computer. It protects against malware — not against a poorly made backup, nor against someone who takes control of it.
Self-custody: Holding your own keys rather than entrusting them to a platform. You depend on no one; you are also solely responsible for backups, security and access for your loved ones.
Exchange (custodial): A service that holds the keys for you. Convenient for buying; in case of bankruptcy, account freeze or hack, your bitcoin shares the platform's fate. On death, access depends on its procedure and your jurisdiction.
2-of-3 multisig: A wallet controlled by three separate keys, two of which are needed to sign. One stolen key is not enough; a lost key can be replaced. It is the foundation of family custody: keys can be spread across several places and several people. See multisig security.
Configuration backup (descriptor): The file that describes how a multisig wallet is put together: which keys, which threshold. Without it, even with two keys out of three, recovering the funds becomes very difficult. It is not as secret as the keys, but it must be backed up and passed on.
Test transaction: Sending a small amount first to check that a new setup works — receiving, then spending — before moving the bulk of your funds. An often-skipped step that prevents irreversible mistakes.
Recovery drill: Regaining access to a wallet from the backups alone, on a blank device, as if the original had disappeared. It is the only way to know whether your backups really work. Repeat it periodically, and with the people who will one day have to do it. Assess my setup.
Time-lock (delayed backup key): A mechanism that lets a backup key spend only after a set period of inactivity. It provides access for your loved ones without giving them that power today.
Address: The public identifier for receiving bitcoin. It can be shared freely; it gives no access to the funds. Always check an address on the device's screen, not only on the computer.
Phishing and fake support: The most common scams: an email, a call or "technical support" pushing you to enter your recovery phrase. No manufacturer, no platform, no serious advisor will ever ask for your words.
Single point of failure: Any element whose loss or compromise is enough to lose everything: a single key, a single copy, a single person who knows. A good setup aims to leave none.
Digital asset inventory: The list of what exists: wallets, platforms, devices, backups, and where each one is — without ever writing down the secrets themselves. It is the first page of any continuity plan, and the first thing distraught relatives look for.
Access protocol: The document, kept up to date and tested, that says who can access what, how, in what order, and whom to call. It does not contain the keys; it explains how the distributed keys come together when the time comes. Prepare the hand-over.
Family continuity plan: The whole package: inventory, key distribution, access protocol, trained relatives, coordination with the notary, annual review. Its purpose is not to prepare for a death, but to ensure access never depends on a single person. See the continuity plan.
Notary and digital assets: The notary includes digital assets in the estate and can keep a sealed copy of the access instructions. They cannot recover a lost key or break into a wallet: the technical side must be prepared during the holder's lifetime.
Fixed fees: Payment agreed in advance and paid by the client alone, independent of the amounts held and with no commission from any manufacturer, software or platform. It is what allows an advisor to recommend what fits, and only that. See our offers.