1. the quality or state of behaving in a silly, foolish, or comical manner; lack of dignity or seriousness
Usage: uncountable; often used to describe behavior that is deliberately funny or inappropriately humorous
2. crude or boorish behavior; lack of manners or social grace
Usage: uncountable; emphasizes rudeness or lack of sophistication

Examples

• The comedian's clownishness delighted the children in the audience.
• His constant clownishness made it difficult for others to take him seriously at work.
• The actor abandoned all clownishness to deliver a powerful dramatic performance.
• Her clownishness during the formal dinner was considered inappropriate by the other guests.
• The team's clownishness in the locker room helped them bond and stay relaxed before the game.
• Despite his clownishness, he was actually quite intelligent and thoughtful.