Being hyperactive or hyper is a state of being excessively active or energetic. Antonyms for this word could include being calm, relaxed, or serene. These words suggest a state of tranquility and peace rather than high energy levels. Being focused, attentive, or composed are also antonyms for being hyper. These words suggest a sense of control, direction, and stability. Being restless or agitated, on the other hand, would be synonymous with being hyper or hyperactive. So, it is often helpful to consider the context to best determine the appropriate antonyms for a particular use of the word "being hyper.