The word "unhinged" typically means something or someone that is mentally unstable or emotionally disturbed. Antonyms for this term could include stable, grounded, composed, rational, and balanced. These words imply a sense of order, control, and reasoning. Other possible antonyms may be steady, level-headed, sensible, calm or collected. Using these antonyms can help to create a contrast or balance in your writing, making it more effective and impactful. By choosing the right words to describe a situation or person, you can help to convey a specific message or emotion to your readers or listeners.