False Rejection

When a biometric system fails to identify an applicant or fails to verify the legitimate claimed identity of an applicant.
SOURCE: SP 800-76

In biometrics, the instance of a security system failing to verify or identify an authorized person. It does not necessarily indicate a flaw in the biometric system; for example, in a fingerprint-based system, an incorrectly aligned finger on the scanner or dirt on the scanner can result in the scanner misreading the fingerprint, causing a false rejection of the authorized user.
SOURCE: CNSSI-4009