from The American Heritage® Dictionary of the English Language, 5th Edition.

  • noun A treatment that enhances an existing medical regimen, as a pharmacological agent added to a drug to increase or aid its effect.
  • noun An immunological agent that increases the antigenic response.
  • adjective Contributing to or enhancing an existing medical regimen.

from The Century Dictionary.

  • Serving to help or assist; auxiliary; contributory: as, an adjuvant medicine.
  • noun A person or thing aiding or helping; whatever aids or assists.
  • noun Specifically In medicine, whatever aids in removing or preventing disease; especially, a substance added to a prescription to aid the operation of the principal ingredient.

from the GNU version of the Collaborative International Dictionary of English.

  • noun rare An assistant.
  • noun (Med.) An ingredient, in a prescription, which aids or modifies the action of the principal ingredient.
  • noun (Immunology) A substance added to an immunogenic agent to enhance the production of antibodies.
  • noun A substance added to a formulation of a drug which enhances the effect of the active ingredient.
  • adjective rare Helping; helpful; assisting.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

  • noun A thing which aids or assists; an auxiliary.
  • noun One who helps or facilitates; an assistant.
  • noun medicine An additive (as in a drug) that aids or modifies the action of the principal ingredient.
  • noun medicine Something (as in a method) that enhances the effectiveness of a medical treatment.
  • noun immunology A substance enhancing the immune response to an antigen.
  • adjective The noun used as a modifier.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

  • noun an additive that enhances the effectiveness of medical treatment
  • adjective furnishing added support
  • adjective enhancing the action of a medical treatment


from The American Heritage® Dictionary of the English Language, 4th Edition

From Latin adiuvāns, adiuvant-, present participle of adiuvāre, to help; see aid.

from Wiktionary, Creative Commons Attribution/Share-Alike License

From Latin adiuvāns, present participle of adiuvāre ("to help"), from ad ("to") + iuvāre ("to help"). First English use recorded in 17th century.


  • To describe this form of treatment, Carbone and his team used the word adjuvant, from the Latin phrase “to help.”

    The Emperor of All Maladies

  • The term adjuvant, from a Latin word meaning "to help," was coined in the 1920s by Gaston Ramon, a veterinarian at the Pasteur Institute in France, who observed that horses given diphtheria toxin had a stronger immune response if they had some inflammation at the injection site.

    NYT > Global Home

  • An adjuvant is a vaccine component that boosts the immune response to the vaccine.


  • If you use an adjuvant, make sure it matches the pesticide label adjuvant recommendation.

    Western Farm Press RSS Feed

  • The fact may indicate the importance of long term adjuvant hormone therapy for ER positive cancer patients.

    BioMed Central - Latest articles

  • The vaccine we have in Canada contains an 'adjuvant' - basically, an element that includes a substance that boosts a person's immune system and increases their response to a vaccine.

    Archive 2009-10-01

  • OTTAWA -- The federal government has ordered 200,000 doses of H1N1 influenza vaccine from Australia so pregnant women who prefer their flu shot without an "adjuvant" -- a booster -- won't have to delay their inoculation.

    Toronto Sun

  • Many of us believe the human body contains an immune system which we evolved to fight off disease, and rather than introduce harmful toxins (that's exactly what a vaccine adjuvant is – its the intended purpose, to be toxic and elicit an immune response to make the vaccine effective), we're willing to take the chance that we might get the flu, and in almost all cases, that means a couple days off work feeling crappy.

    CNN Poll: Majority of adult Americans don't want H1N1 flu shot

  • Second, Antigenics has a so-called adjuvant that improves the efficacy of vaccines.

    Five Stock Picks for Your Recovering Portfolio

  • In the second trial, 894 children aged five to 17 months were enrolled to test the safety and effectiveness of the vaccine using a different adjuvant, which is meant to enhance the immune response to the vaccine.

    ANC Daily News Briefing


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  • "While drug makers prepare a swine flu vaccine in anticipation of a possible outbreak this fall, one of the issues yet to be resolved is whether the shots will contain an adjuvant.

    It's something that allows the immune system to respond with higher levels of effectiveness..."

    Swine Flu Vaccine: What The Heck Is an Adjuvant, Anyway? ABC News, August 11, 2009

    August 19, 2009

  • "U.S. guidelines list pregnant women as a high-priority group for pandemic vaccines, although that is for vaccines without adjuvants, ingredients used to stretch a vaccine's active ingredient."

    Study: Swine Flu Strikes Pregnant Women Hard, AP, July 29, 2009

    July 30, 2009