His judgment remained unclouded by any emotional interference.

unclouded 是由前缀 un-（表示“不、无”）和形容词 clouded（被遮蔽的、模糊的）组成的形容词。clouded 来自动词 cloud（使模糊、使阴暗），加上 -ed 变成形容词。unclouded 字面意思是“未被遮蔽的”，引申为“清晰的、不受干扰的”。