An adjuvant may be any compound that when added to a liquid spray, chemical application, formulation or tank mix will either facilitate the mixing, application, or effectiveness of that product or application in some prescribed manner. Adjuvants may be chemically or biologically active compounds, and may typically be used to improve the effectiveness of the products they are added to, either increasing its desired impact and/or decreasing the total amount of formulation needed to achieve that impact.
Among others forms, adjuvants may be offered as water conditioners, surface active agents, spreaders and stickers, deposition agents, pH buffers, crop oils and many others.