a. [ L. adjuvans, p. pr. of adjuvare to aid: cf. F. adjuvant. See Aid. ] Helping; helpful; assisting. [ R. ] “Adjuvant causes.” Howell. [ 1913 Webster ]

n. [ L. adjuvamentum, fr. adjuvare to help; ad + juvare to help. ] 1. An assistant. [ R. ] Yelverton. AS [ 1913 Webster ]

2. (Med.) An ingredient in a prescription drug, which aids or modifies the action of the principal ingredient. AS [ 1913 Webster ]

3. (Med., Immunology) A substance that non-specifically enhances immune response to an antigen, such as by enhancing the production of antibodies. AS [ AS ]