Antonyms for the term "rendered inert" could include words such as animated, active, lively, energetic, or dynamic. These words suggest motion, life, and activity, and are the opposite of being inert. Other antonyms could include words like functional, effective, potent, or powerful, which speak to the ability to perform or carry out a task. These words suggest the opposite of a state of being rendered inert, which implies an inability to perform or act. Whatever the antonym, the opposite of being inert is a state of motion, power, and activity.