Passkey
termsecuritycryptography
A public-private key pair created for one specific site, where the private key never leaves the authenticator and the browser will only offer it to the exact origin it was registered for.
The absence of a shared secret is useful - a breached server database yields public keys - but origin binding is the actual innovation. On a lookalike domain the passkey does not appear, and a signature produced for the wrong origin is rejected by the real site, so the user cannot be talked into a mistake the browser will not make. Synced passkeys inherit the security of the platform account holding them, which is a fair trade for consumer services and a deliberate decision to review for administrative access.
Also known as: discoverable credential, synced passkey, device-bound passkey