ADJUVANT

I. adjective see: aid Date: 1574 serving to aid or contribute ; auxiliary , assisting in the prevention, amelioration, or cure of disease , II. noun Date: 1609 one that helps or facilitates: as, an ingredient (as in a prescription or a solution) that modifies the action of the principal ingredient, something (as a drug or method) that enhances the effectiveness of medical treatment , a substance (as one added to a vaccine) enhancing the immune response to an antigen