negative

Definition of negative test result
National Cancer Institute

negative test result

(NEH-guh-tiv ... reh-ZULT)
A test result that shows the substance or condition the test is supposed to find is not present at all or is present, but in normal amounts. In genetics, a negative test result usually means that a person does not have a mutation (change) in the gene, chromosome, or protein that is being tested. More testing may be needed to make sure a negative test result is correct.

Source: NCI Dictionary of Cancer Terms