The antonyms for the word "most convulsive" would be "calm," "peaceful," "composed," "tranquil," and "serene." These words all convey a sense of stillness and lack of movement, making them the opposite of convulsive. A calm environment is one that is quiet and peaceful, with no sudden outbursts or movements. A peaceful environment is one that is free from tension and turmoil, providing a sense of contentment and relaxation. Composed conveys a sense of being in control of oneself, showing no signs of restlessness or nervousness. Tranquil refers to a state of peacefulness, where there is a feeling of being undisturbed and relaxed. Serene conveys a sense of tranquility and inner peace, where there is no chaos or turbulence.