In pharmacology, an adjuvant is a drug or other substance, or a combination of substances, that is used to increase the efficacy or potency of certain drugs. Specifically, the term can refer to:

• Adjuvant therapy in cancer management

• Analgesic adjuvant in pain management

• Immunologic adjuvant in vaccines

Pesticide adjuvants are chemicals applied alongside pesticides to enhance the effectiveness of the active ingredient.