At the party, a man dressed as a clown acted like a buffoon, making everyone laugh with his silly performance.

buffoon 是名词，来自意大利语 buffone（小丑、滑稽演员），指故意做出愚蠢或夸张行为来逗乐他人的人，常带有贬义色彩，暗示缺乏尊严或智慧。