Regular key
Plain definition. A regular key is a second key pair you can attach to an XRP Ledger account and use to sign transactions instead of the master key pair, protecting the account.
Technical definition. The SetRegularKey transaction is used to assign, change, or remove the regular key pair associated with an account, and an account holder can sign with that pair instead of the master key pair whenever possible. Its optional RegularKey field is a base-58-encoded address that indicates the regular key pair to be assigned; it must not match the master key pair for the address, and leaving it out removes any existing regular key pair. If the regular key pair is compromised but the master key pair is not, a SetRegularKey transaction can be used to regain control of the account.
On this site
On this site, Regular key comes up in Is XRP’s cryptography at risk from quantum computers? and What XRP Ledger features can protect my account (regular keys, multi-signing, disabling the master key)?.
Source
SetRegularKey (xrpl.org), read October 1, 2026.