More spastic is a term used to describe a condition characterized by involuntary muscle movements and spasms. Antonyms for this term would be words that describe a lack of such movements, such as calm, composed, and tranquil. Other antonyms could include controlled, steady, and relaxed. These words would suggest a contrasting state of being, in which the individual's movements are not erratic or sudden. While there may be medical conditions that cause spastic movements, it is important to use language that is respectful and sensitive to the individual's experience, and to avoid stigmatizing terms.