Astasia is a medical term that refers to the inability to stand or maintain a stable posture due to uncontrolled movements. There are a few synonyms for this term that can be used interchangeably in different contexts. One of the most common synonyms for astasia is ataxia, which is also a medical term used to describe a lack of muscle coordination. Another synonym for astasia is dyskinesia, which refers to any involuntary movement disorder. Athetosis is another synonym for astasia that describes a type of dyskinesia characterized by slow, writhing movements of the hands, feet, and limbs. Overall, these synonyms can help convey different aspects of the same medical condition depending on the specific context.