"Staid on" is a phrase that refers to someone or something that is serious, stable, and dependable. However, there are several antonyms to this word that convey the opposite meaning. For instance, the antonyms for "staid on" can be lively, spontaneous, unpredictable, colorful, and radical. If something is lively, it is full of energy, fun, and excitement. Spontaneous describes things that happen naturally without any planning or forethought. Unpredictability means uncertainty or inconsistency. The word colorful implies that something is vibrant, bright, and cheerful. Lastly, radical suggests something that is unorthodox, innovative, or adventurous. All these antonyms can be used to describe things that are opposite to the nature of "staid on.