Plain English Meaning
People the FAA has approved to give the flight tests and sign off the certificates that an FAA inspector would otherwise give. They work in private practice but carry FAA authority during the test.
Full Definition
Private citizens authorized by the FAA to administer practical tests (checkrides) and issue pilot and instructor certificates on the agency's behalf. They are not FAA employees, but they act under FAA authority when conducting these tests.
Context Anchor
Seen when discussing flight instructor qualifications, student preparation for practical tests, and the final check before a pilot certificate or rating is issued.
Derivation
Designated means appointed or chosen for a . Examiner comes from Latin examinare, to weigh or test. Together: someone specifically chosen to test pilots on behalf of the FAA.