Thixotropy is a property of certain materials that become less viscous when subjected to stress or agitation. This means that a thick substance can flow more easily when stirred or shaken, but will return to its original, thicker state when left undisturbed. Common examples of thixotropic materials include paint, gelatin, and some types of clay. This behavior is important in various applications, such as in the formulation of cosmetics and food products, where a smooth application or consistency is desired. Understanding thixotropy helps manufacturers create products that are easy to use while maintaining stability over time.