The antonym for stabilise is destabilise. Destabilise means to cause instability or to make something less stable or secure. It can refer to political, social or economic situations or it can be used to describe the physical properties of an object. Other antonyms for stabilise include fluctuate, waver, unbalance, unsettle, tip, and totter. These words describe movements or actions that can cause something to become unstable or insecure. In contrast, stabilise means to make something steady, secure, or balanced. It is an important concept in engineering, physics, and other industries where stability is critical to ensure safety and performance.