Technical Definition

Passphrase (25th word)

A wallet passphrase is optional additional input used with a recovery phrase to derive a different set of wallet keys and addresses.

By Crypto University Editorial
Seed phraseDerivation pathPrivate key

✦ Key Insight

A passphrase can add protection if a recovery phrase is exposed, but forgetting or mistyping it can permanently prevent access to the intended wallet.

✕ Common Misconceptions

It is not literally required to be one "25th word." Never assume a forgotten passphrase can be recovered.

Detailed Explanation

It is commonly called the "25th word" when used with a 24-word recovery phrase, although it can be a longer string rather than a single word. Every different passphrase produces a different wallet.

In Practice

“The same 24-word phrase used with two different passphrases produces two separate sets of accounts.”

Dig Deeper

Hardware Wallet

A dedicated physical device that stores private keys offline and signs transactions internally.

Private Key

The secret number that authorises spending from a crypto address.

Seed Phrase

A list of 12 or 24 ordinary words that is the master key to every account in your wallet.

Derivation path

A derivation path identifies where a particular key or account is generated within a hierarchical deterministic wallet's key tree.