false-negative

noun Also false negative.

1. Medicine/Medical.
   1. a test result that is incorrect because the test failed to recognize an existing condition or finding.
   2. a person who receives this test result.
2. 1. any screening test result that failed to detect a person or thing being sought: Let’s hope the new body scanner doesn’t give us any false-negatives.
   2. a person or thing that is missed by such a test: Retrain your spam filter if you’re getting too many false-negatives in your inbox.

adjective

3. pertaining to or being a false-negative.