false positivenoun [ C ]
uk/ˌfɒls ˈpɒz.ə.tɪv//ˌfɑːls ˈpɑː.zə.t̬ɪv/a result of a scientific test that appears to show something exists or is present, when this is not correct:
The anthrax test is unreliable because it produces too many false positives.