Which term signifies a pesticide's compatibility when mixed with other substances?

The term that signifies a pesticide's compatibility when mixed with other substances is "Compatibility." This concept is crucial in pesticide application because it refers to how well a pesticide can mix with other chemicals, such as fertilizers, adjuvants, or other pesticides, without causing any adverse reactions.

When compatibility is ensured, it helps prevent issues such as precipitation, phase separation, or the breakdown of the active ingredients, which can diminish effectiveness or create harmful byproducts. Properly understanding compatibility is essential for achieving optimal pesticide performance and ensuring safety during application, thus protecting both the environment and the user.

The other terms mentioned do not specifically pertain to the compatibility of mixtures. Reactivity refers to how a substance might chemically react with other substances, which can be an entirely different consideration. Solubility relates to how well a substance dissolves in a solvent, while volatility describes how readily a substance will vaporize at a given temperature. These concepts, while important in their own right, do not directly address the aspect of mixing pesticides with other materials.