When it comes to describing someone as mentally sound, there are a number of synonyms that can be used to convey the same meaning. Some possible options include emotionally stable, psychologically healthy, mentally balanced, cognitively sound, mentally robust, and mentally resilient. These words all suggest a state of mental wellness and the absence of any serious psychological or emotional problems. Whether you are describing a person's overall mental state, their ability to handle stress or other challenges, or their capacity for self-reflection and personal growth, these synonyms can help you find the right words to express yourself clearly and effectively.