quake in one's boots

The phrase "quake in one's boots" is an idiom that means to feel intense fear or dread. It describes the trembling or shaking sensation one may experience when faced with a highly alarming or intimidating situation. The phrase implies that the fear is so strong that it trembles one's legs or whole body, as if causing their boots to shake. It's a figurative expression used to convey a person's extreme fright or anxiety.