blocking antibody

noun

1. Immunology. an antibody that partly combines with an antigen and interferes with cell-mediated immunity, thereby preventing an allergic reaction.

n.

1. An antibody that combines with an antigen without a reaction but that blocks another antibody from later combining with that antigen.
2. An immunoglobulin that combines specifically with an atopic allergen but does not elicit an allergic reaction.