The term 'Cause of Some Quaking' can be answered by two crossword solutions: FEAR (4 letters) and Panic Attack (11 letters). FEAR is an emotion that is triggered by a perceived threat, and it is often accompanied by physical reactions such as increased heart rate, sweating, and shaking. Panic Attack is an intense episode of FEAR or anxiety that can cause physical symptoms such as chest pain, shortness of breath, and trembling. Both FEAR and Panic Attack can be causes of quaking, which is an involuntary shaking of the body.