The antonyms for the word "in-activating" would be "activating", "energizing", "stimulating", "enabling", "enlivening", "revitalizing", and "awakening". These terms are used to describe the opposite effect of inactivating, which means to make something inactive, unproductive, or ineffective. Instead, activating refers to the process of making something more active, productive, effective, or lively. The opposite of in-activating is often used in the context of body movements, chemical reactions, or technology by making them efficient, functional or reactive, and helps them to achieve a desired outcome.