The correct option is Orphaned Azure Active Directory object.

This term describes a user account that remains in Azure Active Directory after the corresponding on premises Active Directory account has been removed. When the on premises object is deleted but the cloud record was not removed or was converted to a cloud only account it is considered an Orphaned Azure Active Directory object. Resolving an Orphaned Azure Active Directory object typically requires verifying the source of authority and then running a proper sync or performing a manual cleanup in Azure AD.

The term Stale Azure AD entry is informal and not the official Microsoft term for this situation. Stale suggests outdated data but Microsoft documentation uses more precise terms for object state.

The term Azure AD Connect synchronization artifact refers to internal synchronization metadata or connector objects used by the sync engine and not to a user account that remains in Azure AD after the on premises account is deleted. That phrase does not match the standard description of the remaining cloud user.

The term Ghost Azure AD object is colloquial and not used in official Microsoft documentation. It is not the formal name for an account that persists in Azure AD after the on premises account is removed.

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