1. the quality of being clear and easy to understand
2. the quality of thinking clearly and rationally

Examples

• The professor’s lucidness made even complex theories accessible to students.
• Her writing is admired for its lucidness and precision.
• Despite his age, his mental lucidness remained sharp.
• The lucidness of the instructions helped us complete the task quickly.
• After the medication wore off, his lucidness gradually returned.
• The report’s lucidness impressed the board members.