The quality of being easily understood, completely intelligible, or comprehensible. The lucidity of the professor's explanation made the complex topic accessible to all students.
The ability to think clearly, especially in intervals between periods of confusion or insanity. During moments of lucidity, the patient was able to recognize family members and engage in conversation.
The quality of being transparent or clear to the sight, especially of a liquid or the atmosphere. The remarkable lucidity of the alpine lake allowed us to see the colorful stones on the lakebed.