Definition of adjuvant in US English:



  • (of therapy) applied after initial treatment for cancer, especially to suppress secondary tumor formation.

    • ‘Three patients received no adjuvant treatment, and no information on adjuvant therapy was available for the remaining 4 patients.’
    • ‘If surgical removal of a tumor is the primary therapy, then chemotherapy or radiation therapy is considered adjuvant therapy.’
    • ‘The book is divided into five short chapters that cover coping with the diagnosis of cancer, surgical treatments, adjuvant therapies, and ongoing recovery.’
    • ‘Women with breast cancer may benefit from adjuvant chemotherapy, hormonal therapy, or both.’
    • ‘However, this trial suggests that use of high doses of antioxidants as adjuvant therapy might compromise radiation treatment efficacy.’
    additional, auxiliary, supporting, helping, assisting, extra, supplementary, supplemental, accessory, contributory, attendant
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  • A substance which enhances the body's immune response to an antigen.

    • ‘A well-known practical application of this observation is the use of microbe-derived adjuvants to increase antibody responses.’
    • ‘The products use a large amount of organisms and adjuvants such as aluminum hydroxide or oil to produce a sufficient immune response.’
    • ‘Recently, there has been a great deal of interest in biologic agents as potential adjuvants in the treatment of chronic wounds.’
    • ‘Natural oils may turn out to be valuable adjuvants or even replacements for many anti-germicidals under a variety of conditions.’
    • ‘New TB adjuvants (enhancers of the immune response) have been studied.’


Late 16th century: from Latin adjuvant- ‘helping towards’, from the verb adjuvare, from ad- ‘towards’ + juvare to ‘help’.