seronegative

adjective Medicine/Medical.

1. showing no significant level of serum antibodies, or other immunologic marker in the serum, that would indicate previous exposure to the infectious agent being tested.

adjective

1. (of a person whose blood has been tested for a specific disease, such as AIDS) showing no serological reaction indicating the presence of the disease

adj.

1. Having a negative reaction to a serological test for a disease, especially to a test for syphilis or AIDS.